High severity · published Jan 15, 2026
CVE-2026-22045
Traefik's ACME TLS-ALPN fast path lacks timeouts and close on handshake stall
7.5
CVSS
0.3%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TR
traefik · traefik
< 2.11.35; >=3.0.0-beta1, < 3.6.7 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-22045
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-22045
Patch
https://github.com/traefik/traefik/commit/e9f3089e9045812bcf1b410a9d40568917b26c3d
Release Notes
https://github.com/traefik/traefik/releases/tag/v2.11.35
Release Notes
https://github.com/traefik/traefik/releases/tag/v3.6.7
Patch
https://github.com/traefik/traefik/security/advisories/GHSA-cwjm-3f7h-9hwq
More from traefik
10.0
CVE-2026-54763
Traefik: headerField underscore-variant identity spoofing in BasicAuth / DigestAuth / ForwardAuth
10.0
CVE-2026-53622
Traefik: HTTP/3 mTLS bypass via exact SNI TLSOptions lookup for wildcard and mixed-case hosts
10.0
CVE-2026-48491
Traefik: SNICheck ignores wildcard TLSOptions mappings, allowing domain-fronted mTLS bypass
10.0
CVE-2026-48020
Traefik StripPrefix Route-Level Auth Bypass via Path Normalization
10.0
CVE-2026-39858
Traefik: Forwarded alias spoofing top pre-auth decision bypass