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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-20 16:29 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7838 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
traefik traefik Affected: < 2.11.35
Affected: >=3.0.0-beta1, < 3.6.7
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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