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.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-cwjm-3f7h-9hwq Traefik's ACME TLS-ALPN fast path lacks timeouts and close on handshake stall
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 21 Jan 2026 02:15:00 +0900

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 16 Jan 2026 23:15:00 +0900

Type Values Removed Values Added
First Time appeared Traefik
Traefik traefik
Vendors & Products Traefik
Traefik traefik

Fri, 16 Jan 2026 21:15:00 +0900

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Moderate


Fri, 16 Jan 2026 07:45:00 +0900

Type Values Removed Values Added
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.
Title Traefik's ACME TLS-ALPN fast path lacks timeouts and close on handshake stall
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-01-20T16:29:37.648Z

Reserved: 2026-01-05T22:30:38.720Z

Link: CVE-2026-22045

cve-icon Vulnrichment

Updated: 2026-01-20T16:29:31.728Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-01-15T23:15:51.593

Modified: 2026-01-16T15:55:12.257

Link: CVE-2026-22045

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-01-15T22:44:05Z

Links: CVE-2026-22045 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-01-16T22:42:25Z

Weaknesses