CVE-2026-22045
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.35%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.35% probability · 28th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Affected
- traefik/traefik
- Source
- security-advisories@github.com
References
- https://github.com/traefik/traefik/commit/e9f3089e9045812bcf1b410a9d40568917b26c3dPatch
- https://github.com/traefik/traefik/releases/tag/v2.11.35Release Notes
- https://github.com/traefik/traefik/releases/tag/v3.6.7Release Notes
- https://github.com/traefik/traefik/security/advisories/GHSA-cwjm-3f7h-9hwqPatch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.