CVE-2026-88878

Traefik is an HTTP reverse proxy and load balancer. In versions >= v2.8.2 through <= v2.11.55 and >= v3.0.0 through <= v3.7.11, the entryPoints.<name>.transport.respondingTimeouts settings — notably readTimeout, which is enabled by default at 60s — are not applied to the HTTP/3 request path. readTimeout is enforced as a deadline on the underlying TCP connection, which cannot be applied to a QUIC stream, and Traefik's HTTP/3 server is constructed without any timeout. As a result, on entry points with HTTP/3 enabled, an unauthenticated remote client that trickles request body bytes can hold a request open indefinitely and, with it, one upstream connection per request, exhausting bounded backend connection pools and causing denial of service. The issue was introduced in v2.8.2 when a quic-go API change removed the embedded http.Server that carried these timeouts. Fixed in v2.11.56 and v3.7.12.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/security/advisories/GHSA-7ghq-v6jf-g56c	Patch Vendor Advisory
https://www.vulncheck.com/advisories/traefik-2.8.2-through-3.6-http-3-timeout-bypass	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:traefik:traefik::::::::
	cpe:2.3:a:traefik:traefik::::::::

History

No history.

Information

Published : 2026-09-10 14:17

Updated : 2026-09-14 19:58

NVD link : CVE-2026-88878

Mitre link : CVE-2026-88878

CVE.ORG link : CVE-2026-88878

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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