NULL pointer dereference in Coredns
CVE-2026-62309
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.
EPSS: 0.007 (48.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Coredns — versions < 1.14.4
- Coredns.io Coredns
Weakness classification (CWE)
References
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-62309?
- CVE-2026-62309 is a high-severity vulnerability in Coredns, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2026-07-16.
- How severe is CVE-2026-62309?
- High severity. CVSS v3 base score is 7.5 out of 10.