MidnightBSD

Advisories for coredns.io

CVE-2022-2835

A flaw was found in coreDNS. This flaw allows a malicious user to reroute internal calls to some internal services that were accessed by the FQDN in a format of <service>.<namespace>.svc.

CVSS 3.x

Source Score Severity Vector Exploitability Impact
nvd@nist.gov 4.4 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N 1.8 2.5

Products Affected

Vendor Product Version
coredns.io coredns -
CVE-2022-2837

A flaw was found in coreDNS. This flaw allows a malicious user to redirect traffic intended for external top-level domains (TLD) to a pod they control by creating projects and namespaces that match the TLD.

CVSS 3.x

Source Score Severity Vector Exploitability Impact
nvd@nist.gov 6.1 MEDIUM CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N 2.8 2.7

Products Affected

Vendor Product Version
coredns.io coredns -
CVE-2023-30464

CoreDNS through 1.10.1 enables attackers to achieve DNS cache poisoning and inject fake responses via a birthday attack.

Products Affected

Vendor Product Version
coredns.io coredns *
CVE-2025-47950

CoreDNS is a DNS server that chains plugins. In versions prior to 1.12.2, a Denial of Service (DoS) vulnerability exists in the CoreDNS DNS-over-QUIC (DoQ) server implementation. The server previously created a new goroutine for every incoming QUIC stream without imposing any limits on the number of concurrent streams or goroutines. A remote, unauthenticated attacker could open a large number of streams, leading to uncontrolled memory consumption and eventually causing an Out Of Memory (OOM) crash — especially in containerized or memory-constrained environments. The patch in version 1.12.2 introduces two key mitigation mechanisms: `max_streams`, which caps the number of concurrent QUIC streams per connection with a default value of `256`; and `worker_pool_size`, which Introduces a server-wide, bounded worker pool to process incoming streams with a default value of `1024`. This eliminates the 1:1 stream-to-goroutine model and ensures that CoreDNS remains resilient under high concurrency. Some workarounds are available for those who are unable to upgrade. Disable QUIC support by removing or commenting out the `quic://` block in the Corefile, use container runtime resource limits to detect and isolate excessive memory usage, and/or monitor QUIC connection patterns and alert on anomalies.

CVSS 3.x

Source Score Severity Vector Exploitability Impact
security-advisories@github.com 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 3.9 3.6

Products Affected

Vendor Product Version
coredns.io coredns *
CVE-2026-26017

CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a logical vulnerability in CoreDNS allows DNS access controls to be bypassed due to the default execution order of plugins. Security plugins such as acl are evaluated before the rewrite plugin, resulting in a Time-of-Check Time-of-Use (TOCTOU) flaw. This issue has been patched in version 1.14.2.

CVSS 3.x

Source Score Severity Vector Exploitability Impact
security-advisories@github.com 7.7 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N 3.1 4.0

Products Affected

Vendor Product Version
coredns.io coredns *
CVE-2026-26018

CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a denial of service vulnerability exists in CoreDNS's loop detection plugin that allows an attacker to crash the DNS server by sending specially crafted DNS queries. The vulnerability stems from the use of a predictable pseudo-random number generator (PRNG) for generating a secret query name, combined with a fatal error handler that terminates the entire process. This issue has been patched in version 1.14.2.

CVSS 3.x

Source Score Severity Vector Exploitability Impact
security-advisories@github.com 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 3.9 3.6

Products Affected

Vendor Product Version
coredns.io coredns *