6.3

CVE-2026-32595: Traefik: BasicAuth Middleware Timing Attack Allows Username Enumeration

Analyzed
AliasesGHSA-g3hg-j4jv-cwfrGO-2026-4792CGA-5j53-vq89-v6jx
Published 20-03-2026Last modified 20-03-2026

Vulnerability summary

CVE-2026-32595 is a medium (CVSS 6.3) Observable Timing Discrepancy vulnerability in traefik. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 33.3% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.3, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.3/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.39%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 4 · Related 5
OPENSUSE-SU-2026:10444-1OPENSUSE-SU-2026:10445-1OPENSUSE-SU-2026:21483-1SUSE-SU-2026:1135-1CGA-988Q-XJ85-J2PC

Timeline

  1. 20-03-2026
    PublishedVulnerability first disclosed.
  2. 20-03-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.39%

Chance of exploitation in the next 30 days

Percentile

33%

Versus all other CVEs

30-day change

Increase +0.01 pp

From 0.38% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard2 products
  • traefik-3.5All versions (No fix recorded)
  • traefik-fips-3.5All versions (No fix recorded)
Github.com/traefik/traefik2 products
  • v2< 2.11.41
  • v3< 3.6.11 | ≥ 3.7.0-ea.1, < 3.7.0-ea.2
Github.com/traefik1 product
  • traefik≤ 1.7.34 | All versions (No fix recorded)
Traefik1 product
  • traefik≥ 3.0.0-beta1, < 3.6.11 | ≥ 3.7.0-ea.1, < 3.7.0-ea.2 | < 2.11.41 | ≥ 3.0.0, ≤ 3.6.11 | 3.7.0:ea1

4 vendors · 6 products

References

7 links