CVE-2026-26998

MEDIUM EPSS 36.0%
Published Mar 5, 20263mo ago · Modified Mar 6, 20263mo ago
4.4 CVSS 3.1
Medium
Find Similar
Published Mar 5, 2026 3mo ago
Last Modified Mar 6, 2026 3mo ago

Description

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.

CVSS Details

Base Score
4.4
Exploitability
0.7
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity High
Privileges Required High
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
36.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-770

Affected Products 2

VendorProductVersionRange
traefiktraefik* <2.11.38
traefiktraefik*≥3.0.0  –  <3.6.9

References 3

  • github.com https://github.com/traefik/traefik/releases/tag/v2.11.38
    ProductRelease Notes
  • github.com https://github.com/traefik/traefik/releases/tag/v3.6.9
    ProductRelease Notes
  • github.com https://github.com/traefik/traefik/security/advisories/GHSA-fw45-f5q2-2p4x
    PatchVendor Advisory

Remediation

  • github.com https://github.com/traefik/traefik/security/advisories/GHSA-fw45-f5q2-2p4x
    PatchVendor Advisory