CVE-2026-22045 (GCVE-0-2026-22045)

Vulnerability from cvelistv5 – Published: 2026-01-15 22:44 – Updated: 2026-01-20 16:29
VLAI?
Title
Traefik's ACME TLS-ALPN fast path lacks timeouts and close on handshake stall
Summary
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.
Severity ?
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version
traefik traefik Affected: < 2.11.35
Affected: >=3.0.0-beta1, < 3.6.7
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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