CVE-2026-26998 (GCVE-0-2026-26998)

Vulnerability from cvelistv5 – Published: 2026-03-05 16:15 – Updated: 2026-03-06 16:12
VLAI?
Title
Traefik: unbounded io.ReadAll on auth server response body causes OOM denial of service(DOS)
Summary
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.38 and 3.6.9, there is a potential vulnerability in Traefik managing the ForwardAuth middleware responses. When Traefik is configured to use the ForwardAuth middleware, the response body from the authentication server is read entirely into memory without any size limit. There is no maxResponseBodySize configuration to restrict the amount of data read from the authentication server response. If the authentication server returns an unexpectedly large or unbounded response body, Traefik will allocate unlimited memory, potentially causing an out-of-memory (OOM) condition that crashes the process. This results in a denial of service for all routes served by the affected Traefik instance. This issue has been patched in versions 2.11.38 and 3.6.9.
Severity ?
4.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version
traefik traefik Affected: < 2.11.38
Affected: < 3.6.9
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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