High 7.0Published Sep 10, 2026

CVE-2026-88008Traefik: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') and Incorrect Authorization

Updated under an hour ago (2026-10-19 07:10 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for traefik

Exploited in the last 30 days

Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.26 until 2.11.57 and 3.7.13, Traefik forwards a client-supplied Connection header requesting Upgrade, the Upgrade: h2c token, and HTTP2-Settings to a shared backend. If the backend accepts h2c and returns 101 Switching Protocols, Traefik enters a raw tunnel and no longer applies routers, BasicAuth, ForwardAuth, IPAllowList, RateLimit, access logging, metrics, or tracing to later HTTP/2 requests, allowing an unauthenticated request through an unprotected route to reach protected paths on the same backend. This issue is fixed in 2.11.57 and 3.7.13.

CVSS: 7.0 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
Weakness (CWE): CWE-444, CWE-863
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Sep 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

traefik traefik traefik:traefik (from the name)	from 2.11.26, < 2.11.57; from 3.4.2, < 3.7.13	CNA record
traefik traefik traefik:traefik	from 2.11.26 before 2.11.57; from 3.4.2 before 3.7.13	NVD

References

https://github.com/traefik/traefik/security/advisories/GHSA-w4v4-9rw7-5326x-refsource-confirm, patch, vendor-advisory
https://github.com/traefik/traefik/pull/13797x-refsource-misc, issue-tracking, patch
https://github.com/traefik/traefik/commit/a277e94664ffc1ce9543df552d3bbf48d4d3b8b3x-refsource-misc, patch
https://github.com/traefik/traefik/releases/tag/v2.11.57x-refsource-misc, release-notes
https://github.com/traefik/traefik/releases/tag/v3.7.13x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.