Is CVE-2026-62309 being exploited?

No public exploit is currently tracked.

How severe is CVE-2026-62309?

CVE-2026-62309 has a CVSS v3 severity of HIGH (7.5).

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CVE-2026-62309

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.