CVE-2026-22045
CVE-2026-22045 · Traefik's ACME TLS-ALPN fast path lacks timeouts and close on handshake stall
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.35 and 3.6.7, there is a potential vulnerability in Traefik ACME TLS certificates' automatic generation: the ACME TLS-ALPN fast path can allow unauthenticated clients to tie up go routines and file descriptors indefinitely when the ACME TLS challenge is enabled. A malicious client can open many connections, send a minimal ClientHello with acme-tls/1, then stop responding, leading to denial of service of the entry point. The vulnerability is fixed in 2.11.35 and 3.6.7.
CVSS 5.9 · Medium · EPSS 0.3%
- Published
- Updated
Stack: web
Affected products and versions
traefik
- Versions
- < 2.11.35: Affected
- >=3.0.0-beta1, < 3.6.7: Affected
No fix published
Original sources
- https://github.com/traefik/traefik/security/advisories/GHSA-cwjm-3f7h-9hwq
- https://github.com/traefik/traefik/commit/e9f3089e9045812bcf1b410a9d40568917b26c3d
- https://github.com/traefik/traefik/releases/tag/v2.11.35
- https://github.com/traefik/traefik/releases/tag/v3.6.7
- https://nvd.nist.gov/vuln/detail/CVE-2026-22045