{"id":"CVE-2026-80218","summary":"Sign-in token minted for one resource accepted by another in AshAuthentication","details":"Improper Authentication vulnerability in team-alembic AshAuthentication allows an attacker holding a sign-in token for one authenticated resource to be signed in as a user of a different resource.\n\nAshAuthentication.Strategy.Password.SignInWithTokenPreparation.extract_primary_keys_from_subject/2 parses the JWT sub claim (for example user?id=1) with URI.parse/1 and keeps only its query string, discarding the path segment that names the subject the token was issued for. Nothing else restores that binding: AshAuthentication.Jwt.verify/3 checks the signature, exp, nbf, jti and the library-version claims, the purpose check only requires sign_in, and the remaining comparison is over primary-key field names, which are identical across resources. The WebAuthn sign-in and remember-me preparations carry copies of the same helper and drop the path in the same way. The magic link sign-in path pins the subject name against the resource and is not affected.\n\nThis issue affects ash_authentication: from 3.10.5 before 4.15.0 and from 5.0.0-rc.0 before 5.0.0-rc.14.","aliases":["EEF-CVE-2026-80218","GHSA-3pr8-f99q-86hp"],"modified":"2026-09-20T11:30:50.222997461Z","published":"2026-09-17T13:09:25.585Z","database_specific":{"unresolved_ranges":[{"extracted_events":[{"introduced":"eca8cadea0f1595ed2c10a0c177b1da9aa9e5269"},{"fixed":"*"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"EEF","cwe_ids":["CWE-287"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80218.json"},"references":[{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-80218.html"},{"type":"WEB","url":"https://github.com"},{"type":"WEB","url":"https://osv.dev/vulnerability/EEF-CVE-2026-80218"},{"type":"WEB","url":"https://repo.hex.pm"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80218.json"},{"type":"ADVISORY","url":"https://github.com/team-alembic/ash_authentication/security/advisories/GHSA-3pr8-f99q-86hp"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80218"},{"type":"FIX","url":"https://github.com/team-alembic/ash_authentication/commit/2640e1872e1fef4e4606e601bf00102cff784c03"},{"type":"FIX","url":"https://github.com/team-alembic/ash_authentication/commit/7baac243ca651eee127a84d672eee3fcff42e598"},{"type":"FIX","url":"https://github.com/team-alembic/ash_authentication/commit/eca8cadea0f1595ed2c10a0c177b1da9aa9e5269"},{"type":"PACKAGE","url":"https://github.com/team-alembic/ash_authentication"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/team-alembic/ash_authentication","events":[{"introduced":"2e9ea281ac0a408ed940465a38c59467b9b98e91"},{"fixed":"d6b2be35cf8f0b8ab84e7a934cfb0d91de0a3c17"},{"introduced":"6767fe27eb952e5bc09aa2e5a7d8f96f5a1c424a"},{"fixed":"fea75958a081ed337ceb578396174039694c48df"},{"fixed":"2640e1872e1fef4e4606e601bf00102cff784c03"},{"fixed":"7baac243ca651eee127a84d672eee3fcff42e598"},{"fixed":"eca8cadea0f1595ed2c10a0c177b1da9aa9e5269"}],"database_specific":{"source":["DESCRIPTION","REFERENCES"],"extracted_events":[{"introduced":"3.10.5"},{"fixed":"4.15.0"},{"introduced":"5.0.0-rc.0"},{"fixed":"5.0.0-rc.14"}]}}],"versions":["v4.14.2","v5.0.0-rc.13","v4.14.1","v5.0.0-rc.12","v5.0.0-rc.11","v5.0.0-rc.10","v4.14.0","v4.13.7","5.0.0-rc.9","5.0.0-rc.8","v5.0.0-rc.7","v5.0.0-rc.6","v5.0.0-rc.5","v5.0.0-rc.4","v5.0.0-rc.3","v5.0.0-rc.2","v5.0.0-rc.1","v5.0.0-rc.0","v4.13.6","v4.13.5","v4.13.4","v4.13.3","v4.13.2","v4.13.1","v4.13.0","v4.12.0","v4.11.0","v4.10.0","v4.9.9","v4.9.8","v4.9.7","v4.9.6","v4.9.5","v4.9.4","v4.9.3","v4.9.2","v4.9.1","v4.9.0","v4.8.7","v4.8.5","v4.8.4","v4.8.3","v4.8.2","v4.8.1","v4.8.0","v4.7.7","v4.7.6","v4.7.5","v4.7.4","v4.7.3","v4.7.2","v4.7.1","v4.7.0","v4.6.4","v4.6.3","v4.6.2","v4.6.1","v4.6.0","v4.5.6","v4.5.5","v4.5.4","v4.5.3","v4.5.2","v4.5.1","v4.4.9","v4.4.8","v4.4.7","v4.4.6","v4.4.5","v4.4.4","v4.4.3","v4.4.2","v4.4.1","v4.4.0","v4.3.12","v4.3.10","v4.3.9","v4.3.7","v4.3.6","v4.3.4","v4.3.3","v4.3.2","v4.3.1","v4.3.0","v4.2.7","v4.2.5","v4.2.3","v4.2.2","v4.2.1","v4.2.0","v4.1.0","v4.0.4","v4.0.3","v4.0.2","v4.0.1","v4.0.0","v4.0.0-rc.7","v4.0.0-rc.6","v4.0.0-rc.5","v4.0.0-rc.4","v4.0.0-rc.3","v4.0.0-rc.2","v4.0.0-rc.1","v4.0.0-rc.0","v3.12.4","v3.12.3","v3.12.2","v3.12.1","v3.12.0","v3.11.16","v3.11.15","v3.11.14","v3.11.13","v3.11.12","v3.11.10","v3.11.9","v3.11.8","v3.11.7","v3.11.6","v3.11.5","v3.11.4","v3.11.3","v3.11.2","v3.11.1","v3.11.0","v3.10.8","v3.10.7","v3.10.6","v3.10.5"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80218.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"}]}