Medium severity · published Sep 10, 2026
CVE-2026-88012
Traefik: respondingTimeouts.readTimeout is not applied to HTTP/3, leaving slow-body uploads unbounded
5.3
CVSS
0.5%
EPSS
No
On KEV
Description
Traefik is an open source HTTP reverse proxy and load balancer. From 2.8.2 until 2.11.56 and 3.7.12, HTTP/3 entrypoints do not apply entryPoints..transport.respondingTimeouts.readTimeout because the timeout is enforced on a TCP connection and the HTTP/3 server has no corresponding QUIC stream deadline. An unauthenticated client can use a slow request body, trickling data indefinitely while holding a request and an upstream connection open and exhausting backends with bounded connection pools. This issue is fixed in 2.11.56 and 3.7.12.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TR
traefik · traefik
>= 2.8.2, < 2.11.56; >= 3.0.0, < 3.7.12 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-88012
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-88012
Patch
https://github.com/traefik/traefik/commit/a8d0bc425859dde7481a6c9a324e610b81d754d0
Issue Tracking
https://github.com/traefik/traefik/pull/13717
Patch
https://github.com/traefik/traefik/releases/tag/v2.11.56
Patch
https://github.com/traefik/traefik/releases/tag/v3.7.12
Patch
https://github.com/traefik/traefik/security/advisories/GHSA-7ghq-v6jf-g56c
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