{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-71326","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-08-05T18:14:42.065Z","datePublished":"2026-08-06T16:34:23.931Z","dateUpdated":"2026-08-08T02:12:44.764Z"},"containers":{"cna":{"title":"Traefik: BasicAuth singleflight key collision allows authenticated identity spoofing","problemTypes":[{"descriptions":[{"cweId":"CWE-287","lang":"en","description":"CWE-287: Improper Authentication","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"HIGH","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":2.1,"baseSeverity":"LOW","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/traefik/traefik/security/advisories/GHSA-6765-c87h-8mrf","tags":["x_refsource_CONFIRM"],"url":"https://github.com/traefik/traefik/security/advisories/GHSA-6765-c87h-8mrf"},{"name":"https://github.com/traefik/traefik/pull/13572","tags":["x_refsource_MISC"],"url":"https://github.com/traefik/traefik/pull/13572"},{"name":"https://github.com/traefik/traefik/commit/b5ace8eb5d6779980567f5e75efd2d9e08b7e350","tags":["x_refsource_MISC"],"url":"https://github.com/traefik/traefik/commit/b5ace8eb5d6779980567f5e75efd2d9e08b7e350"},{"name":"https://github.com/traefik/traefik/releases/tag/v3.6.25","tags":["x_refsource_MISC"],"url":"https://github.com/traefik/traefik/releases/tag/v3.6.25"},{"name":"https://github.com/traefik/traefik/releases/tag/v3.7.10","tags":["x_refsource_MISC"],"url":"https://github.com/traefik/traefik/releases/tag/v3.7.10"}],"affected":[{"vendor":"traefik","product":"traefik","versions":[{"version":">= 3.6.11, < 3.6.25","status":"affected"},{"version":">= 3.7.0, < 3.7.10","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-08-06T16:34:23.931Z"},"descriptions":[{"lang":"en","value":"Traefik is an open source HTTP reverse proxy and load balancer. From 3.6.11 until 3.6.25 and 3.7.10, Traefik's BasicAuth middleware in pkg/middlewares/auth/basic_auth.go deduplicates concurrent password checks with a singleflight key built from the delimiter-free concatenation of password and secret, allowing an attacker who has a valid credential and the stored hash to authenticate as an unconfigured username when headerField trusts the forwarded identity. This issue is fixed in 3.6.25 and 3.7.10."}],"source":{"advisory":"GHSA-6765-c87h-8mrf","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-08T02:12:30.362636Z","id":"CVE-2026-71326","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-08-08T02:12:44.764Z"}}]}}