CVE-2026-32595 (GCVE-0-2026-32595)

Vulnerability from cvelistv5 – Published: 2026-03-20 10:08 – Updated: 2026-03-20 15:38
VLAI?
Title
Traefik: BasicAuth Middleware Timing Attack Allows Username Enumeration
Summary
Traefik is an HTTP reverse proxy and load balancer. Versions 2.11.40 and below, 3.0.0-beta1 through 3.6.11, and 3.7.0-ea.1 comtain BasicAuth middleware that allows username enumeration via a timing attack. When a submitted username exists, the middleware performs a bcrypt password comparison taking ~166ms. When the username does not exist, the response returns immediately in ~0.6ms. This ~298x timing difference is observable over the network and allows an unauthenticated attacker to reliably distinguish valid from invalid usernames. This issue is patched in versions 2.11.41, 3.6.11 and 3.7.0-ea.2.
Severity ?
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N
CWE
  • CWE-208 - Observable Timing Discrepancy
Assigner
References
Impacted products
Vendor Product Version
traefik traefik Affected: < 2.11.41
Affected: >= 3.0.0-beta1, < 3.6.11
Affected: >= 3.7.0-ea.1, < 3.7.0-ea.2
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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