Vulnerability in fetchmail 5.5.0-2 and earlier in the AUTHENTICATE GSSAPI command.

A buffer overflow in Linux fetchmail before 5.8.6 allows remote attackers to execute arbitrary code via a large 'To:' field in an email header.

Fetchmail (aka fetchmail-ssl) before 5.8.17 allows a remote malicious (1) IMAP server or (2) POP/POP3 server to overwrite arbitrary memory and possibly gain privileges via a negative index number as part of a response to a LIST request.

fetchmailconf in fetchmail before 5.7.4 allows local users to overwrite files of other users via a symlink attack on temporary files.

fetchmail email client before 5.9.10 does not properly limit the maximum number of messages available, which allows a remote IMAP server to overwrite memory via a message count that exceeds the boundaries of an array.

Buffer overflows in Fetchmail 6.0.0 and earlier allow remote attackers to cause a denial of service (crash) or execute arbitrary code via (1) long headers that are not properly processed by the readheaders function, or (2) via long Received: headers, which are not properly parsed by the parse_received function.

The getmxrecord function in Fetchmail 6.0.0 and earlier does not properly check the boundary of a particular malformed DNS packet from a malicious DNS server, which allows remote attackers to cause a denial of service (crash) when Fetchmail attempts to read data beyond the expected boundary.

Heap-based buffer overflow in Fetchmail 6.1.3 and earlier does not account for the "@" character when determining buffer lengths for local addresses, which allows remote attackers to execute arbitrary code via a header with a large number of local addresses.

Fetchmail 6.2.4 and earlier does not properly allocate memory for long lines, which allows remote attackers to cause a denial of service (crash) via a certain email.

Buffer overflow in the POP3 client in Fetchmail before 6.2.5.2 allows remote POP3 servers to cause a denial of service and possibly execute arbitrary code via long UIDL responses. NOTE: a typo in an advisory accidentally used the wrong CVE identifier for the Fetchmail issue. This is the correct identifier.

fetchmailconf before 1.49 in fetchmail 6.2.0, 6.2.5 and 6.2.5.2 creates configuration files with insecure world-readable permissions, which allows local users to obtain sensitive information such as passwords.

fetchmail before 6.3.1 and before 6.2.5.5, when configured for multidrop mode, allows remote attackers to cause a denial of service (application crash) by sending messages without headers from upstream mail servers.

fetchmail 6.3.0 and other versions before 6.3.2 allows remote attackers to cause a denial of service (crash) via crafted e-mail messages that cause a free of an invalid pointer when fetchmail bounces the message to the originator or local postmaster.

The sdump function in sdump.c in fetchmail 6.3.11, 6.3.12, and 6.3.13, when running in verbose mode on platforms for which char is signed, allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via an SSL X.509 certificate containing non-printable characters with the high bit set, which triggers a heap-based buffer overflow during escaping.

fetchmail 4.6.3 through 6.3.16, when debug mode is enabled, does not properly handle invalid characters in a multi-character locale, which allows remote attackers to cause a denial of service (memory consumption and application crash) via a crafted (1) message header or (2) POP3 UIDL list.

fetchmail 5.9.9 through 6.3.19 does not properly limit the wait time after issuing a (1) STARTTLS or (2) STLS request, which allows remote servers to cause a denial of service (application hang) by acknowledging the request but not sending additional packets.

report_vbuild in report.c in Fetchmail before 6.4.20 sometimes omits initialization of the vsnprintf va_list argument, which might allow mail servers to cause a denial of service or possibly have unspecified other impact via long error messages. NOTE: it is unclear whether use of Fetchmail on any realistic platform results in an impact beyond an inconvenience to the client user.

Fetchmail before 6.4.22 fails to enforce STARTTLS session encryption in some circumstances, such as a certain situation with IMAP and PREAUTH.