Description
CoreDNS is a DNS server that chains plugins. Prior to version 1.14.0, multiple CoreDNS server implementations (gRPC, HTTPS, and HTTP/3) lack critical resource-limiting controls. An unauthenticated remote attacker can exhaust memory and degrade or crash the server by opening many concurrent connections, streams, or sending oversized request bodies. The issue is similar in nature to CVE-2025-47950 (QUIC DoS) but affects additional server types that do not enforce connection limits, stream limits, or message size constraints. Version 1.14.0 contains a patch.
Affected products
coredns.io: coredns
References3
- github.com/coredns/coredns/commit/0d8cbb1a6bcb6bc9c1a489865278b… Patch
- github.com/coredns/coredns/pull/7490 Issue TrackingPatch
- github.com/coredns/coredns/security/advisories/GHSA-527x-5wrf-2… Third Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
6.6
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 43 · as of 11 November 2026
- CWE
- CWE-770
Could this be exploited in your environment?
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