{"cve":"CVE-2026-88010","nvd":{"published":"2026-09-22T16:18:06.963","modified":"2026-10-29T17:08:46.137","status":"Analyzed","description":"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.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","score":6.3},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","score":5.3},"cwes":["CWE-208"],"references":["https://github.com/traefik/traefik/commit/ddc1bf4660b85fd61fafdd821eb8216fb1a0b130","https://github.com/traefik/traefik/pull/13816","https://github.com/traefik/traefik/releases/tag/v3.7.13","https://github.com/traefik/traefik/security/advisories/GHSA-8fcf-v89g-xpg6"],"products":["traefik:traefik"],"source":"nvd","synced_at":"2026-10-29T17:36:52.580905486+00:00"},"epss":{"cve":"CVE-2026-88010","score":0.00691,"percentile":0.52747,"date":"2026-10-29"},"kev":null,"osv":[{"id":"GHSA-8fcf-v89g-xpg6","url":"https://osv.dev/vulnerability/GHSA-8fcf-v89g-xpg6","summary":"Traefik: BasicAuth singleflight coalescing reintroduces an unauthenticated username-enumeration timing oracle","modified":"2026-10-01T20:55:42.797529432Z","packages":[{"ecosystem":"Go","name":"Traefik","purl":"pkg:golang/Traefik","ranges":[">=3.6.11 <3.7.13"],"fixed":["3.7.13"]}]},{"id":"GO-2026-6558","url":"https://osv.dev/vulnerability/GO-2026-6558","summary":"Traefik: BasicAuth singleflight coalescing reintroduces an unauthenticated username-enumeration timing oracle","modified":"2026-10-01T20:45:13.180305525Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","ranges":["all versions"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}