CVE-2026-26018: high-severity vulnerability in coredns
CoreDNS Loop Detection Denial of Service Vulnerability
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 1.2%
CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a denial of service vulnerability exists in CoreDNS's loop detection plugin that allows an attacker to crash the DNS server by sending specially crafted DNS queries. The vulnerability stems from the use of a predictable pseudo-random number generator (PRNG) for generating a secret query name, combined with a fatal error handler that terminates the entire process. This issue has been patched in version 1.14.2.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
coredns · corednsRelated CVEs — coredns
In the same product, most dangerous first.
CVE-2025-47950HIGHCoreDNS Vulnerable to DoQ Memory Exhaustion via Stream AmplificationEPSS 1.2%CVE-2026-32936HIGHCoreDNS DoH GET path missing size validation causes CPU and memory amplificationEPSS 0.7%CVE-2026-62309HIGHCoreDNS: proxyproto plugin panics on PPv2 datagram with non-UDP transport — single 28-byte packet remote DoSEPSS 0.7%CVE-2026-35579HIGHCoreDNS TSIG authentication bypass on gRPC, QUIC, DoH, and DoH3 transportsEPSS 0.6%CVE-2026-82399HIGHCoreDNS: Unauthenticated memory exhaustion in custom transportsEPSS 0.6%CVE-2026-62299MEDIUMCoreDNS: rewrite-plugin EDNS0 response-revert nil-pointer panic (remote DoS) when a downstream plugin returns a response with no OPT recordEPSS 0.5%
References
https://access.redhat.com/errata/RHSA-2026:25127https://access.redhat.com/errata/RHSA-2026:36873https://access.redhat.com/errata/RHSA-2026:8151https://access.redhat.com/security/cve/CVE-2026-26018https://bugzilla.redhat.com/show_bug.cgi?id=2445242https://github.com/coredns/coredns/releases/tag/v1.14.2https://github.com/coredns/coredns/security/advisories/GHSA-h75p-j8xm-m278https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26018.json