CVE-2026-26018
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.12%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.12% probability · 64th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-337, CWE-400, CWE-770, CWE-1241
- Affected
- coredns.io/coredns
- Source
- security-advisories@github.com
References
- https://github.com/coredns/coredns/releases/tag/v1.14.2Product, Release Notes
- https://github.com/coredns/coredns/security/advisories/GHSA-h75p-j8xm-m278Exploit, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:25127
- https://access.redhat.com/errata/RHSA-2026:36873
- https://access.redhat.com/errata/RHSA-2026:8151
- https://access.redhat.com/security/cve/CVE-2026-26018
- https://bugzilla.redhat.com/show_bug.cgi?id=2445242
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26018.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.