os._execvpe from os.py in Python 2.2.1 and earlier creates temporary files with predictable names, which could allow local users to execute arbitrary code via a symlink attack.

Buffer overflow in the getaddrinfo function in Python 2.2 before 2.2.2, when IPv6 support is disabled, allows remote attackers to execute arbitrary code via an IPv6 address that is obtained using DNS.

The SimpleXMLRPCServer library module in Python 2.2, 2.3 before 2.3.5, and 2.4, when used by XML-RPC servers that use the register_instance method to register an object without a _dispatch method, allows remote attackers to read or modify globals of the associated module, and possibly execute arbitrary code, via dotted attributes.

Stack-based buffer overflow in Python 2.4.2 and earlier, running on Linux 2.6.12.5 under gcc 4.0.3 with libc 2.3.5, allows local users to cause a "stack overflow," and possibly gain privileges, by running a script from a current working directory that has a long name, related to the realpath function. NOTE: this might not be a vulnerability. However, the fact that it appears in a programming language interpreter could mean that some applications are affected, although attack scenarios might be limited because the attacker might already need to cross privilege boundaries to cause an exploitable program to be placed in a directory with a long name; or, depending on the method that Python uses to determine the current working directory, setuid applications might be affected.

Buffer overflow in the repr function in Python 2.3 through 2.6 before 20060822 allows context-dependent attackers to cause a denial of service and possibly execute arbitrary code via crafted wide character UTF-32/UCS-4 strings to certain scripts.

Off-by-one error in the PyLocale_strxfrm function in Modules/_localemodule.c for Python 2.4 and 2.5 causes an incorrect buffer size to be used for the strxfrm function, which allows context-dependent attackers to read portions of memory via unknown manipulations that trigger a buffer over-read due to missing null termination.

Directory traversal vulnerability in the (1) extract and (2) extractall functions in the tarfile module in Python allows user-assisted remote attackers to overwrite arbitrary files via a .. (dot dot) sequence in filenames in a TAR archive, a related issue to CVE-2001-1267.

Multiple integer overflows in the imageop module in Python 2.5.1 and earlier allow context-dependent attackers to cause a denial of service (application crash) and possibly obtain sensitive information (memory contents) via crafted arguments to (1) the tovideo method, and unspecified other vectors related to (2) imageop.c, (3) rbgimgmodule.c, and other files, which trigger heap-based buffer overflows.

Multiple integer overflows in imageop.c in Python before 2.5.3 allow context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via crafted images that trigger heap-based buffer overflows. NOTE: this issue is due to an incomplete fix for CVE-2007-4965.

Multiple integer overflows in Python 2.5.2 and earlier allow context-dependent attackers to have an unknown impact via vectors related to the (1) stringobject, (2) unicodeobject, (3) bufferobject, (4) longobject, (5) tupleobject, (6) stropmodule, (7) gcmodule, and (8) mmapmodule modules. NOTE: The expandtabs integer overflows in stringobject and unicodeobject in 2.5.2 are covered by CVE-2008-5031.

Integer overflow in _hashopenssl.c in the hashlib module in Python 2.5.2 and earlier might allow context-dependent attackers to defeat cryptographic digests, related to "partial hashlib hashing of data exceeding 4GB."

Multiple integer overflows in Python before 2.5.2 might allow context-dependent attackers to have an unknown impact via vectors related to (1) Include/pymem.h; (2) _csv.c, (3) _struct.c, (4) arraymodule.c, (5) audioop.c, (6) binascii.c, (7) cPickle.c, (8) cStringIO.c, (9) cjkcodecs/multibytecodec.c, (10) datetimemodule.c, (11) md5.c, (12) rgbimgmodule.c, and (13) stropmodule.c in Modules/; (14) bufferobject.c, (15) listobject.c, and (16) obmalloc.c in Objects/; (17) Parser/node.c; and (18) asdl.c, (19) ast.c, (20) bltinmodule.c, and (21) compile.c in Python/, as addressed by "checks for integer overflows, contributed by Google."

Multiple integer overflows in the PyOS_vsnprintf function in Python/mysnprintf.c in Python 2.5.2 and earlier allow context-dependent attackers to cause a denial of service (memory corruption) or have unspecified other impact via crafted input to string formatting operations. NOTE: the handling of certain integer values is also affected by related integer underflows and an off-by-one error.

Untrusted search path vulnerability in the PySys_SetArgv API function in Python 2.6 and earlier, and possibly later versions, prepends an empty string to sys.path when the argv[0] argument does not contain a path separator, which might allow local users to execute arbitrary code via a Trojan horse Python file in the current working directory.

Buffer underflow in the rgbimg module in Python 2.5 allows remote attackers to cause a denial of service (application crash) via a large ZSIZE value in a black-and-white (aka B/W) RGB image that triggers an invalid pointer dereference.

Integer overflow in rgbimgmodule.c in the rgbimg module in Python 2.5 allows remote attackers to have an unspecified impact via a large image that triggers a buffer overflow. NOTE: this vulnerability exists because of an incomplete fix for CVE-2008-3143.12.

Multiple buffer overflows in the RLE decoder in the rgbimg module in Python 2.5 allow remote attackers to have an unspecified impact via an image file containing crafted data that triggers improper processing within the (1) longimagedata or (2) expandrow function.

Multiple integer overflows in audioop.c in the audioop module in Python 2.6, 2.7, 3.1, and 3.2 allow context-dependent attackers to cause a denial of service (application crash) via a large fragment, as demonstrated by a call to audioop.lin2lin with a long string in the first argument, leading to a buffer overflow. NOTE: this vulnerability exists because of an incorrect fix for CVE-2008-3143.5.

The audioop module in Python 2.7 and 3.2 does not verify the relationships between size arguments and byte string lengths, which allows context-dependent attackers to cause a denial of service (memory corruption and application crash) via crafted arguments, as demonstrated by a call to audioop.reverse with a one-byte string, a different vulnerability than CVE-2010-1634.

The asyncore module in Python before 3.2 does not properly handle unsuccessful calls to the accept function, and does not have accompanying documentation describing how daemon applications should handle unsuccessful calls to the accept function, which makes it easier for remote attackers to conduct denial of service attacks that terminate these applications via network connections.

Multiple race conditions in smtpd.py in the smtpd module in Python 2.6, 2.7, 3.1, and 3.2 alpha allow remote attackers to cause a denial of service (daemon outage) by establishing and then immediately closing a TCP connection, leading to the accept function having an unexpected return value of None, an unexpected value of None for the address, or an ECONNABORTED, EAGAIN, or EWOULDBLOCK error, or the getpeername function having an ENOTCONN error, a related issue to CVE-2010-3492.

The is_cgi method in CGIHTTPServer.py in the CGIHTTPServer module in Python 2.5, 2.6, and 3.0 allows remote attackers to read script source code via an HTTP GET request that lacks a / (slash) character at the beginning of the URI.

The urllib and urllib2 modules in Python 2.x before 2.7.2 and 3.x before 3.2.1 process Location headers that specify redirection to file: URLs, which makes it easier for remote attackers to obtain sensitive information or cause a denial of service (resource consumption) via a crafted URL, as demonstrated by the file:///etc/passwd and file:///dev/zero URLs.

virtualenv.py in virtualenv before 1.5 allows local users to overwrite arbitrary files via a symlink attack on a certain file in /tmp/.

The list_directory function in Lib/SimpleHTTPServer.py in SimpleHTTPServer in Python before 2.5.6c1, 2.6.x before 2.6.7 rc2, and 2.7.x before 2.7.2 does not place a charset parameter in the Content-Type HTTP header, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks against Internet Explorer 7 via UTF-7 encoding.

The XML parser (xmlparse.c) in expat before 2.1.0 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via an XML file with many identifiers with the same value.

The utf-16 decoder in Python 3.1 through 3.3 does not update the aligned_end variable after calling the unicode_decode_call_errorhandler function, which allows remote attackers to obtain sensitive information (process memory) or cause a denial of service (memory corruption and crash) via unspecified vectors.

expat before version 2.4.0 does not properly handle entities expansion unless an application developer uses the XML_SetEntityDeclHandler function, which allows remote attackers to cause a denial of service (resource consumption), send HTTP requests to intranet servers, or read arbitrary files via a crafted XML document, aka an XML External Entity (XXE) issue. NOTE: it could be argued that because expat already provides the ability to disable external entity expansion, the responsibility for resolving this issue lies with application developers; according to this argument, this entry should be REJECTed, and each affected application would need its own CVE.

easy_install in setuptools before 0.7 uses HTTP to retrieve packages from the PyPI repository, and does not perform integrity checks on package contents, which allows man-in-the-middle attackers to execute arbitrary code via a crafted response to the default use of the product.

The gzip_decode function in the xmlrpc client library in Python 3.4 and earlier allows remote attackers to cause a denial of service (memory consumption) via a crafted HTTP request.

The py-bcrypt module before 0.3 for Python does not properly handle concurrent memory access, which allows attackers to bypass authentication via multiple authentication requests, which trigger the password hash to be overwritten.

Algorithmic complexity vulnerability in the ssl.match_hostname function in Python 3.2.x, 3.3.x, and earlier, and unspecified versions of python-backports-ssl_match_hostname as used for older Python versions, allows remote attackers to cause a denial of service (CPU consumption) via multiple wildcard characters in the common name in a certificate.

The ssl.match_hostname function in the SSL module in Python 2.6 through 3.4 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

Python 2.7 before 3.4 only uses the last eight bits of the prefix to randomize hash values, which causes it to compute hash values without restricting the ability to trigger hash collisions predictably and makes it easier for context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table. NOTE: this vulnerability exists because of an incomplete fix for CVE-2012-1150.

Python before 3.3.4 RC1 allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a file size value larger than the size of the zip file to the (1) ZipExtFile.read, (2) ZipExtFile.read(n), (3) ZipExtFile.readlines, (4) ZipFile.extract, or (5) ZipFile.extractall function.

The ssl.match_hostname function in CPython (aka Python) before 2.7.9 and 3.x before 3.3.3 does not properly handle wildcards in hostnames, which might allow man-in-the-middle attackers to spoof servers via a crafted certificate.

OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly restrict processing of ChangeCipherSpec messages, which allows man-in-the-middle attackers to trigger use of a zero-length master key in certain OpenSSL-to-OpenSSL communications, and consequently hijack sessions or obtain sensitive information, via a crafted TLS handshake, aka the "CCS Injection" vulnerability.

The parser cache functionality in parsergenerator.py in RPLY (aka python-rply) before 0.7.1 allows local users to spoof cache data by pre-creating a temporary rply-*.json file with a predictable name.

Race condition in the xdg.BaseDirectory.get_runtime_dir function in python-xdg 0.25 allows local users to overwrite arbitrary files by pre-creating /tmp/pyxdg-runtime-dir-fallback-victim to point to a victim-owned location, then replacing it with a symlink to an attacker-controlled location once the get_runtime_dir function is called.

Requests (aka python-requests) before 2.3.0 allows remote servers to obtain a netrc password by reading the Authorization header in a redirected request.

Requests (aka python-requests) before 2.3.0 allows remote servers to obtain sensitive information by reading the Proxy-Authorization header in a redirected request.

Buffer overflow in the socket.recvfrom_into function in Modules/socketmodule.c in Python 2.5 before 2.7.7, 3.x before 3.3.4, and 3.4.x before 3.4rc1 allows remote attackers to execute arbitrary code via a crafted string.

The (1) load_djpeg function in JpegImagePlugin.py, (2) Ghostscript function in EpsImagePlugin.py, (3) load function in IptcImagePlugin.py, and (4) _copy function in Image.py in Python Image Library (PIL) 1.1.7 and earlier and Pillow before 2.3.1 do not properly create temporary files, which allow local users to overwrite arbitrary files and obtain sensitive information via a symlink attack on the temporary file.

The (1) JpegImagePlugin.py and (2) EpsImagePlugin.py scripts in Python Image Library (PIL) 1.1.7 and earlier and Pillow before 2.3.1 uses the names of temporary files on the command line, which makes it easier for local users to conduct symlink attacks by listing the processes.

Race condition in the _get_masked_mode function in Lib/os.py in Python 3.2 through 3.5, when exist_ok is set to true and multiple threads are used, might allow local users to bypass intended file permissions by leveraging a separate application vulnerability before the umask has been set to the expected value.

Python Image Library (PIL) 1.1.7 and earlier and Pillow 2.3 might allow remote attackers to execute arbitrary commands via shell metacharacters in unspecified vectors related to CVE-2014-1932, possibly JpegImagePlugin.py.

PIL/IcnsImagePlugin.py in Python Imaging Library (PIL) and Pillow before 2.3.2 and 2.5.x before 2.5.2 allows remote attackers to cause a denial of service via a crafted block size.

The Jpeg2KImagePlugin plugin in Pillow before 2.5.3 allows remote attackers to cause a denial of service via a crafted image.

Array index error in the scanstring function in the _json module in Python 2.7 through 3.5 and simplejson before 2.6.1 allows context-dependent attackers to read arbitrary process memory via a negative index value in the idx argument to the raw_decode function.

The CGIHTTPServer module in Python 2.7.5 and 3.3.4 does not properly handle URLs in which URL encoding is used for path separators, which allows remote attackers to read script source code or conduct directory traversal attacks and execute unintended code via a crafted character sequence, as demonstrated by a %2f separator.

Integer overflow in bufferobject.c in Python before 2.7.8 allows context-dependent attackers to obtain sensitive information from process memory via a large size and offset in a "buffer" function.

The HTTP clients in the (1) httplib, (2) urllib, (3) urllib2, and (4) xmlrpclib libraries in CPython (aka Python) 2.x before 2.7.9 and 3.x before 3.4.3, when accessing an HTTPS URL, do not (a) check the certificate against a trust store or verify that the server hostname matches a domain name in the subject's (b) Common Name or (c) subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.

Pillow before 2.7.0 allows remote attackers to cause a denial of service via a compressed text chunk in a PNG image that has a large size when it is decompressed.

Multiple integer overflows in the XML_GetBuffer function in Expat through 2.1.0, as used in Google Chrome before 44.0.2403.89 and other products, allow remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via crafted XML data, a related issue to CVE-2015-2716.

In Python (aka CPython) up to 3.10.8, the mailcap module does not add escape characters into commands discovered in the system mailcap file. This may allow attackers to inject shell commands into applications that call mailcap.findmatch with untrusted input (if they lack validation of user-provided filenames or arguments). The fix is also back-ported to 3.7, 3.8, 3.9

The resolve_redirects function in sessions.py in requests 2.1.0 through 2.5.3 allows remote attackers to conduct session fixation attacks via a cookie without a host value in a redirect.

Untrusted search path vulnerability in python.exe in Python through 3.5.0 on Windows allows local users to gain privileges via a Trojan horse readline.pyd file in the current working directory. NOTE: the vendor says "It was determined that this is a longtime behavior of Python that cannot really be altered at this point."

Expat allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a malformed input document, which triggers a buffer overflow.

Buffer overflow in the ImagingLibTiffDecode function in libImaging/TiffDecode.c in Pillow before 3.1.1 allows remote attackers to overwrite memory via a crafted TIFF file.

The smtplib library in CPython (aka Python) before 2.7.12, 3.x before 3.4.5, and 3.5.x before 3.5.2 does not return an error when StartTLS fails, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a "StartTLS stripping attack."

Buffer overflow in the ImagingFliDecode function in libImaging/FliDecode.c in Pillow before 3.1.1 allows remote attackers to cause a denial of service (crash) via a crafted FLI file.

TGCaptcha2 version 0.3.0 is vulnerable to a replay attack due to a missing nonce allowing attackers to use a single solved CAPTCHA multiple times.

The CGIHandler class in Python before 2.7.12 does not protect against the HTTP_PROXY variable name clash in a CGI script, which could allow a remote attacker to redirect HTTP requests.

The verify function in the RSA package for Python (Python-RSA) before 3.3 allows attackers to spoof signatures with a small public exponent via crafted signature padding, aka a BERserk attack.

The DES and Triple DES ciphers, as used in the TLS, SSH, and IPSec protocols and other protocols and products, have a birthday bound of approximately four billion blocks, which makes it easier for remote attackers to obtain cleartext data via a birthday attack against a long-duration encrypted session, as demonstrated by an HTTPS session using Triple DES in CBC mode, aka a "Sweet32" attack.

Buffer overflow in the ImagingPcdDecode function in PcdDecode.c in Pillow before 3.1.1 and Python Imaging Library (PIL) 1.1.7 and earlier allows remote attackers to cause a denial of service (crash) via a crafted PhotoCD file.

Heap-based buffer overflow in the j2k_encode_entry function in Pillow 2.5.0 through 3.1.1 allows remote attackers to cause a denial of service (memory corruption) via a crafted Jpeg2000 file.

Use-after-free vulnerability in bzip2recover in bzip2 1.0.6 allows remote attackers to cause a denial of service (crash) via a crafted bzip2 file, related to block ends set to before the start of the block.

Integer overflow in the ImagingResampleHorizontal function in libImaging/Resample.c in Pillow before 3.1.1 allows remote attackers to have unspecified impact via negative values of the new size, which triggers a heap-based buffer overflow.

The overflow protection in Expat is removed by compilers with certain optimization settings, which allows remote attackers to cause a denial of service (crash) or possibly execute arbitrary code via crafted XML data. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-1283 and CVE-2015-2716.

Integer overflow in the get_data function in zipimport.c in CPython (aka Python) before 2.7.12, 3.x before 3.4.5, and 3.5.x before 3.5.2 allows remote attackers to have unspecified impact via a negative data size value, which triggers a heap-based buffer overflow.

CRLF injection vulnerability in the HTTPConnection.putheader function in urllib2 and urllib in CPython (aka Python) before 2.7.10 and 3.x before 3.4.4 allows remote attackers to inject arbitrary HTTP headers via CRLF sequences in a URL.

A HTTP/2 implementation built using any version of the Python priority library prior to version 1.2.0 could be targeted by a malicious peer by having that peer assign priority information for every possible HTTP/2 stream ID. The priority tree would happily continue to store the priority information for each stream, and would therefore allocate unbounded amounts of memory. Attempting to actually use a tree like this would also cause extremely high CPU usage to maintain the tree.

A HTTP/2 implementation built using any version of the Python HPACK library between v1.0.0 and v2.2.0 could be targeted for a denial of service attack, specifically a so-called "HPACK Bomb" attack. This attack occurs when an attacker inserts a header field that is exactly the size of the HPACK dynamic header table into the dynamic header table. The attacker can then send a header block that is simply repeated requests to expand that field in the dynamic table. This can lead to a gigantic compression ratio of 4,096 or better, meaning that 16kB of data can decompress to 64MB of data on the target machine.

Versions 1.17 and 1.18 of the Python urllib3 library suffer from a vulnerability that can cause them, in certain configurations, to not correctly validate TLS certificates. This places users of the library with those configurations at risk of man-in-the-middle and information leakage attacks. This vulnerability affects users using versions 1.17 and 1.18 of the urllib3 library, who are using the optional PyOpenSSL support for TLS instead of the regular standard library TLS backend, and who are using OpenSSL 1.1.0 via PyOpenSSL. This is an extremely uncommon configuration, so the security impact of this vulnerability is low.

An integer overflow during the parsing of XML using the Expat library. This vulnerability affects Firefox < 50.

Pillow before 3.3.2 allows context-dependent attackers to obtain sensitive information by using the "crafted image file" approach, related to an "Integer Overflow" issue affecting the Image.core.map_buffer in map.c component.

Pillow before 3.3.2 allows context-dependent attackers to execute arbitrary code by using the "crafted image file" approach, related to an "Insecure Sign Extension" issue affecting the ImagingNew in Storage.c component.

CPython (aka Python) up to 2.7.13 is vulnerable to an integer overflow in the PyString_DecodeEscape function in stringobject.c, resulting in heap-based buffer overflow (and possible arbitrary code execution)

Lib/webbrowser.py in Python through 3.6.3 does not validate strings before launching the program specified by the BROWSER environment variable, which might allow remote attackers to conduct argument-injection attacks via a crafted URL. NOTE: a software maintainer indicates that exploitation is impossible because the code relies on subprocess.Popen and the default shell=False setting

The Wave_read._read_fmt_chunk function in Lib/wave.py in Python through 3.6.4 does not ensure a nonzero channel value, which allows attackers to cause a denial of service (divide-by-zero and exception) via a crafted wav format audio file. NOTE: the vendor disputes this issue because Python applications "need to be prepared to handle a wide variety of exceptions.

A vulnerability classified as problematic was found in Python 2.7.13. This vulnerability affects unknown code of the component pgAdmin4. The manipulation leads to uncontrolled search path. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used.

An exploitable vulnerability exists in the Databook loading functionality of Tablib 0.11.4. A yaml loaded Databook can execute arbitrary python commands resulting in command execution. An attacker can insert python into loaded yaml to trigger this vulnerability.

Openpyxl 2.4.1 resolves external entities by default, which allows remote attackers to conduct XXE attacks via a crafted .xlsx document.

XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in an infinite loop using a malformed external entity definition from an external DTD.

Python 2.7.14 is vulnerable to a Heap-Buffer-Overflow as well as a Heap-Use-After-Free. Python versions prior to 2.7.14 may also be vulnerable and it appears that Python 2.7.17 and prior may also be vulnerable however this has not been confirmed. The vulnerability lies when multiply threads are handling large amounts of data. In both cases there is essentially a race condition that occurs. For the Heap-Buffer-Overflow, Thread 2 is creating the size for a buffer, but Thread1 is already writing to the buffer without knowing how much to write. So when a large amount of data is being processed, it is very easy to cause memory corruption using a Heap-Buffer-Overflow. As for the Use-After-Free, Thread3->Malloc->Thread1->Free's->Thread2-Re-uses-Free'd Memory. The PSRT has stated that this is not a security vulnerability due to the fact that the attacker must be able to run code, however in some situations, such as function as a service, this vulnerability can potentially be used by an attacker to violate a trust boundary, as such the DWF feels this issue deserves a CVE.

Python Software Foundation CPython version From 3.2 until 3.6.4 on Windows contains a Buffer Overflow vulnerability in os.symlink() function on Windows that can result in Arbitrary code execution, likely escalation of privilege. This attack appears to be exploitable via a python script that creates a symlink with an attacker controlled name or location. This vulnerability appears to have been fixed in 3.7.0 and 3.6.5.

Python Software Foundation Python (CPython) version 2.7 contains a CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection') vulnerability in shutil module (make_archive function) that can result in Denial of service, Information gain via injection of arbitrary files on the system or entire drive. This attack appear to be exploitable via Passage of unfiltered user input to the function. This vulnerability appears to have been fixed in after commit add531a1e55b0a739b0f42582f1c9747e5649ace.

python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in pop3lib's apop() method. An attacker could use this flaw to cause denial of service.

python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method. An attacker could use this flaw to cause denial of service.

Python's elementtree C accelerator failed to initialise Expat's hash salt during initialization. This could make it easy to conduct denial of service attacks against Expat by constructing an XML document that would cause pathological hash collisions in Expat's internal data structures, consuming large amounts CPU and RAM. The vulnerability exists in Python versions 3.7.0, 3.6.0 through 3.6.6, 3.5.0 through 3.5.6, 3.4.0 through 3.4.9, 2.7.0 through 2.7.15.

The Requests package before 2.20.0 for Python sends an HTTP Authorization header to an http URI upon receiving a same-hostname https-to-http redirect, which makes it easier for remote attackers to discover credentials by sniffing the network.

urllib3 before version 1.23 does not remove the Authorization HTTP header when following a cross-origin redirect (i.e., a redirect that differs in host, port, or scheme). This can allow for credentials in the Authorization header to be exposed to unintended hosts or transmitted in cleartext.

Modules/_pickle.c in Python before 3.7.1 has an integer overflow via a large LONG_BINPUT value that is mishandled during a "resize to twice the size" attempt. This issue might cause memory exhaustion, but is only relevant if the pickle format is used for serializing tens or hundreds of gigabytes of data. This issue is fixed in: v3.4.10, v3.4.10rc1; v3.5.10, v3.5.10rc1, v3.5.7, v3.5.7rc1, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.7, v3.6.7rc1, v3.6.7rc2, v3.6.8, v3.6.8rc1, v3.6.9, v3.6.9rc1; v3.7.1, v3.7.1rc1, v3.7.1rc2, v3.7.2, v3.7.2rc1, v3.7.3, v3.7.3rc1, v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.

http.cookiejar.DefaultPolicy.domain_return_ok in Lib/http/cookiejar.py in Python before 3.7.3 does not correctly validate the domain: it can be tricked into sending existing cookies to the wrong server. An attacker may abuse this flaw by using a server with a hostname that has another valid hostname as a suffix (e.g., pythonicexample.com to steal cookies for example.com). When a program uses http.cookiejar.DefaultPolicy and tries to do an HTTP connection to an attacker-controlled server, existing cookies can be leaked to the attacker. This affects 2.x through 2.7.16, 3.x before 3.4.10, 3.5.x before 3.5.7, 3.6.x before 3.6.9, and 3.7.x before 3.7.3.

zlib before 1.2.12 allows memory corruption when deflating (i.e., when compressing) if the input has many distant matches.

urllib3 before 1.24.2 does not remove the authorization HTTP header when following a cross-origin redirect (i.e., a redirect that differs in host, port, or scheme). This can allow for credentials in the authorization header to be exposed to unintended hosts or transmitted in cleartext. NOTE: this issue exists because of an incomplete fix for CVE-2018-20060 (which was case-sensitive).

A flaw was discovered in the python-novajoin plugin, all versions up to, excluding 1.1.1, for Red Hat OpenStack Platform. The novajoin API lacked sufficient access control, allowing any keystone authenticated user to generate FreeIPA tokens.

A security regression of CVE-2019-9636 was discovered in python since commit d537ab0ff9767ef024f26246899728f0116b1ec3 affecting versions 2.7, 3.5, 3.6, 3.7 and from v3.8.0a4 through v3.8.0b1, which still allows an attacker to exploit CVE-2019-9636 by abusing the user and password parts of a URL. When an application parses user-supplied URLs to store cookies, authentication credentials, or other kind of information, it is possible for an attacker to provide specially crafted URLs to make the application locate host-related information (e.g. cookies, authentication data) and send them to a different host than where it should, unlike if the URLs had been correctly parsed. The result of an attack may vary based on the application.

In the urllib3 library through 1.24.1 for Python, CRLF injection is possible if the attacker controls the request parameter.

The urllib3 library before 1.24.2 for Python mishandles certain cases where the desired set of CA certificates is different from the OS store of CA certificates, which results in SSL connections succeeding in situations where a verification failure is the correct outcome. This is related to use of the ssl_context, ca_certs, or ca_certs_dir argument.

A code injection issue was discovered in PyXDG before 0.26 via crafted Python code in a Category element of a Menu XML document in a .menu file. XDG_CONFIG_DIRS must be set up to trigger xdg.Menu.parse parsing within the directory containing this file. This is due to a lack of sanitization in xdg/Menu.py before an eval call.

BZ2_decompress in decompress.c in bzip2 through 1.0.6 has an out-of-bounds write when there are many selectors.

The MSI installer for Python through 2.7.16 on Windows defaults to the C:\Python27 directory, which makes it easier for local users to deploy Trojan horse code. (This also affects old 3.x releases before 3.5.) NOTE: the vendor's position is that it is the user's responsibility to ensure C:\Python27 access control or choose a different directory, because backwards compatibility requires that C:\Python27 remain the default for 2.7.x

In libexpat before 2.2.8, crafted XML input could fool the parser into changing from DTD parsing to document parsing too early; a consecutive call to XML_GetCurrentLineNumber (or XML_GetCurrentColumnNumber) then resulted in a heap-based buffer over-read.

An issue was discovered in Python through 2.7.16, 3.x through 3.5.7, 3.6.x through 3.6.9, and 3.7.x through 3.7.4. The email module wrongly parses email addresses that contain multiple @ characters. An application that uses the email module and implements some kind of checks on the From/To headers of a message could be tricked into accepting an email address that should be denied. An attack may be the same as in CVE-2019-11340; however, this CVE applies to Python more generally.

An issue was discovered in Pillow before 6.2.0. When reading specially crafted invalid image files, the library can either allocate very large amounts of memory or take an extremely long period of time to process the image.

The documentation XML-RPC server in Python through 2.7.16, 3.x through 3.6.9, and 3.7.x through 3.7.4 has XSS via the server_title field. This occurs in Lib/DocXMLRPCServer.py in Python 2.x, and in Lib/xmlrpc/server.py in Python 3.x. If set_server_title is called with untrusted input, arbitrary JavaScript can be delivered to clients that visit the http URL for this server.

library/glob.html in the Python 2 and 3 documentation before 2016 has potentially misleading information about whether sorting occurs, as demonstrated by irreproducible cancer-research results. NOTE: the effects of this documentation cross application domains, and thus it is likely that security-relevant code elsewhere is affected. This issue is not a Python implementation bug, and there are no reports that NMR researchers were specifically relying on library/glob.html. In other words, because the older documentation stated "finds all the pathnames matching a specified pattern according to the rules used by the Unix shell," one might have incorrectly inferred that the sorting that occurs in a Unix shell also occurred for glob.glob. There is a workaround in newer versions of Willoughby nmr-data_compilation-p2.py and nmr-data_compilation-p3.py, which call sort() directly.

An issue was discovered in urllib2 in Python 2.x through 2.7.17 and urllib in Python 3.x through 3.8.0. CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the host component of a URL) followed by an HTTP header. This is similar to the CVE-2019-9740 query string issue and the CVE-2019-9947 path string issue. (This is not exploitable when glibc has CVE-2016-10739 fixed.). This is fixed in: v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1; v3.6.11, v3.6.11rc1, v3.6.12; v3.7.8, v3.7.8rc1, v3.7.9; v3.8.3, v3.8.3rc1, v3.8.4, v3.8.4rc1, v3.8.5, v3.8.6, v3.8.6rc1.

typed_ast 1.3.0 and 1.3.1 has a handle_keywordonly_args out-of-bounds read. An attacker with the ability to cause a Python interpreter to parse Python source (but not necessarily execute it) may be able to crash the interpreter process. This could be a concern, for example, in a web-based service that parses (but does not execute) Python code. (This issue also affected certain Python 3.8.0-alpha prereleases.)

typed_ast 1.3.0 and 1.3.1 has an ast_for_arguments out-of-bounds read. An attacker with the ability to cause a Python interpreter to parse Python source (but not necessarily execute it) may be able to crash the interpreter process. This could be a concern, for example, in a web-based service that parses (but does not execute) Python code. (This issue also affected certain Python 3.8.0-alpha prereleases.)

There is a DoS vulnerability in Pillow before 6.2.2 caused by FpxImagePlugin.py calling the range function on an unvalidated 32-bit integer if the number of bands is large. On Windows running 32-bit Python, this results in an OverflowError or MemoryError due to the 2 GB limit. However, on Linux running 64-bit Python this results in the process being terminated by the OOM killer.

In Lib/tarfile.py in Python through 3.8.3, an attacker is able to craft a TAR archive leading to an infinite loop when opened by tarfile.open, because _proc_pax lacks header validation.

An exploitable denial-of-service vulnerability exists in the X509 certificate parser of Python.org Python 2.7.11 / 3.6.6. A specially crafted X509 certificate can cause a NULL pointer dereference, resulting in a denial of service. An attacker can initiate or accept TLS connections using crafted certificates to trigger this vulnerability.

python-gnupg 0.4.3 allows context-dependent attackers to trick gnupg to decrypt other ciphertext than intended. To perform the attack, the passphrase to gnupg must be controlled by the adversary and the ciphertext should be trusted. Related to a "CWE-20: Improper Input Validation" issue affecting the affect functionality component.

CRLF Injection in pypiserver 1.2.5 and below allows attackers to set arbitrary HTTP headers and possibly conduct XSS attacks via a %0d%0a in a URI.

Python 2.7.x through 2.7.16 and 3.x through 3.7.2 is affected by: Improper Handling of Unicode Encoding (with an incorrect netloc) during NFKC normalization. The impact is: Information disclosure (credentials, cookies, etc. that are cached against a given hostname). The components are: urllib.parse.urlsplit, urllib.parse.urlparse. The attack vector is: A specially crafted URL could be incorrectly parsed to locate cookies or authentication data and send that information to a different host than when parsed correctly. This is fixed in: v2.7.17, v2.7.17rc1, v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1, v3.5.7, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.9, v3.6.9rc1; v3.7.3, v3.7.3rc1, v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.

Lib/zipfile.py in Python through 3.7.2 allows remote attackers to cause a denial of service (resource consumption) via a ZIP bomb.

An issue was discovered in urllib2 in Python 2.x through 2.7.16 and urllib in Python 3.x through 3.7.3. CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the query string after a ? character) followed by an HTTP header or a Redis command. This is fixed in: v2.7.17, v2.7.17rc1, v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.9, v3.6.9rc1; v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.

An issue was discovered in urllib2 in Python 2.x through 2.7.16 and urllib in Python 3.x through 3.7.3. CRLF injection is possible if the attacker controls a url parameter, as demonstrated by the first argument to urllib.request.urlopen with \r\n (specifically in the path component of a URL that lacks a ? character) followed by an HTTP header or a Redis command. This is similar to the CVE-2019-9740 query string issue. This is fixed in: v2.7.17, v2.7.17rc1, v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.9, v3.6.9rc1; v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.

urllib in Python 2.x through 2.7.16 supports the local_file: scheme, which makes it easier for remote attackers to bypass protection mechanisms that blacklist file: URIs, as demonstrated by triggering a urllib.urlopen('local_file:///etc/passwd') call.

Pillow before 7.1.0 has multiple out-of-bounds reads in libImaging/FliDecode.c.