CVE-2026-62299: CoreDNS is a DNS server written in Go. Prior to 1.14.5, the CoreDNS rewrite plugin supports edns0 rewrite rules with an optional revert flag, and two response rules, edns0SetRespon

mediumCVSS 5.3CVE-2026-62299

CoreDNS is a DNS server written in Go. Prior to 1.14.5, the CoreDNS rewrite plugin supports edns0 rewrite rules with an optional revert flag, and two response rules, edns0SetResponseRule and edns0ReplaceResponseRule[T] in plugin/rewrite/edns0.go, call res.IsEdns0() and immediately dereference the returned *dns.OPT without a nil check when a downstream plugin returns a response with no OPT record. A remote, unauthenticated client can send a single ordinary DNS query matching a rewrite edns0 <local|nsid|subnet> <set|append|replace> ... revert rule, causing ResponseReverter in plugin/rewrite/reverter.go to panic, return SERVFAIL, and degrade availability, or crash the CoreDNS process if the debug directive disables recovery. This issue is fixed in version 1.14.5.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 5.3
Published: 2026-07-16
Last updated: 2026-07-22
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-62299

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-622990.31% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 24% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-62299	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

mediumCVE-2026-62299: CoreDNS: rewrite-plugin EDNS0 response-revert nil-pointer panic (remote DoS) when a downstream…msrc

Recent advisories for CoreDNS is a

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

medium[NEW] [medium] CoreDNS: Multiple vulnerabilities allow Denial of Servicecert-bund · 2026-07-17
lowCVE-2026-62994: CoreDNS is a DNS server written in Go. From 1.9.4 until 1.14.5, a network DNS client allowed t…nvd · 2026-07-16
highCVE-2026-62309: CoreDNS is a DNS server written in Go. Prior to 1.14.4, a single 28-byte UDP datagram can cras…nvd · 2026-07-16
highCVE-2026-62309: CoreDNS: proxyproto plugin panics on PPv2 datagram with non-UDP transport — single 28-byte pac…msrc · 2026-07-14
mediumCVE-2026-62299: CoreDNS: rewrite-plugin EDNS0 response-revert nil-pointer panic (remote DoS) when a downstream…msrc · 2026-07-14
lowCVE-2026-62994: CoreDNS `k8s_external` headless AXFR can emit an empty transfer batch that panics the `transfe…msrc · 2026-07-14