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TI-2026-60036 Aliases CVE-2026-88010GHSA-8fcf-v89g-xpg6

Traefik: BasicAuth singleflight coalescing reintroduces an unauthenticated username-enumeration timing oracle

Priority LOW 28CWE-208Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-208.

Summary

Traefik is an open source HTTP reverse proxy and load balancer. From 3.6.11 until 3.7.13, checkPassword in pkg/middlewares/auth/basic_auth.go constructs the BasicAuth singleflight key from the submitted password and stored secret. Concurrent requests for absent usernames therefore coalesce on one key while configured usernames perform separate password hashes, creating an unauthenticated timing discrepancy that reveals whether a username exists. Sequential checks remain cost-equalized, Traefik v2 and Digest authentication are not affected, and the issue does not disclose credentials or bypass authentication. This issue is fixed in version 3.7.13.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00307 23rd percentileScored 2026-11-07
Fix Fixed traefik (traefik): 3.7.13github.com/traefik/traefik/v3 (Go): 3.7.13

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
traefiktraefik3.6.11 to before 3.7.133.7.13Patch availableCNA
—github.com/traefik/traefik/v3 (Go)3.6.11 to before 3.7.133.7.13Patch availableGHSA-8fcf-v89g-xpg6
—github.com/traefik/traefik (Go)all versions—No fix listedGHSA-8fcf-v89g-xpg6
  • traefik Vendortraefik Affected 3.6.11 to before 3.7.13 Fixed in 3.7.13 Patch available CNA
  • github.com/traefik/traefik/v3 (Go) Vendor— Affected 3.6.11 to before 3.7.13 Fixed in 3.7.13 Patch available GHSA-8fcf-v89g-xpg6
  • github.com/traefik/traefik (Go) Vendor— Affected all versions Fixed in — No fix listed GHSA-8fcf-v89g-xpg6

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*3.6.11 to before 3.7.13Vulnerabletraefik
  • cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* Versions 3.6.11 to before 3.7.13 Vulnerable ·traefik

Remediation

  • Fix · CNA traefik (traefik) Fixed in 3.7.13
  • Fix · GHSA-8fcf-v89g-xpg6 github.com/traefik/traefik/v3 (Go) Fixed in 3.7.13 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-88010
  2. 2026-10-03 Alias added: GHSA-8fcf-v89g-xpg6
  3. 2026-10-29 CVSS score added · NVD
  4. 2026-10-30 EPSS moved to the below the 50th percentile
  5. 2026-11-04 Fix available: Go/github.com/traefik/traefik/[email protected] · GHSA-8fcf-v89g-xpg6

References

Patch 3

Advisory 1

Other 2

  • TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
  • TI-2023-25774 Uncontrolled Resource Consumption in Traefik CVSS 3.1HIGH 7.5
  • TI-2025-40914 Traefik doesn't Prevent Path Normalization Bypass in Router + Middleware Rules CVSS 4.0MEDIUM 6.9
  • TI-2022-07529 Authorization header displayed in the debug logs CVSS 3.1MEDIUM 6.5
  • TI-2024-30459 HTTP client can remove the X-Forwarded headers in Traefik CVSS 3.1CRITICAL 9.8
  • TI-2026-60261 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect CVSS 4.0CRITICAL 9.3
See all 83 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences