Vulnerability Description
CoreDNS is a DNS server written in Go. Prior to 1.14.4, a single 28-byte UDP datagram can crash the CoreDNS process when the proxyproto plugin is enabled because plugin/pkg/proxyproto/proxyproto.go PacketConn.ReadFrom handles a PROXY v2 header with non-UDP transport such as family byte 0x11, reassigns addr from a nil readFrom result after parseProxyProtocol errors, and calls addr.String() in the warning log before ServeDNS recovery applies. This issue is fixed in version 1.14.4.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Coredns.Io | Coredns | < 1.14.4 |
Related Weaknesses (CWE)
References
- https://github.com/coredns/coredns/commit/60a439dd4febfcd78e3779e952fe3fbf3c16bbPatch
- https://github.com/coredns/coredns/pull/8154Issue TrackingPatch
- https://github.com/coredns/coredns/releases/tag/v1.14.4Release Notes
- https://github.com/coredns/coredns/security/advisories/GHSA-9rvv-m5g5-wc8rExploitThird Party Advisory
FAQ
What is CVE-2026-62309?
CVE-2026-62309 is a vulnerability with a CVSS score of 7.5 (HIGH). CoreDNS is a DNS server written in Go. Prior to 1.14.4, a single 28-byte UDP datagram can crash the CoreDNS process when the proxyproto plugin is enabled because plugin/pkg/proxyproto/proxyproto.go Pa...
How severe is CVE-2026-62309?
CVE-2026-62309 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-62309?
Check the references section above for vendor advisories and patch information. Affected products include: Coredns.Io Coredns.