CVE-2026-62309: Coredns.io Coredns

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

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.

Affected products

• Coredns.io Coredns: before 1.14.4 (fixed in 1.14.4)

Published 2026-07-16. Last modified 2026-07-22.