{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "3.10.5"
              },
              {
                "fixed": "4.15.0"
              },
              {
                "introduced": "5.0.0-rc.0"
              },
              {
                "fixed": "5.0.0-rc.14"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "2e9ea281ac0a408ed940465a38c59467b9b98e91"
            },
            {
              "fixed": "d6b2be35cf8f0b8ab84e7a934cfb0d91de0a3c17"
            },
            {
              "introduced": "6767fe27eb952e5bc09aa2e5a7d8f96f5a1c424a"
            },
            {
              "fixed": "fea75958a081ed337ceb578396174039694c48df"
            },
            {
              "fixed": "2640e1872e1fef4e4606e601bf00102cff784c03"
            },
            {
              "fixed": "7baac243ca651eee127a84d672eee3fcff42e598"
            },
            {
              "fixed": "eca8cadea0f1595ed2c10a0c177b1da9aa9e5269"
            }
          ],
          "repo": "https://github.com/team-alembic/ash_authentication",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-3pr8-f99q-86hp"
  ],
  "database_specific": {
    "cna_assigner": "EEF",
    "cwe_ids": [
      "CWE-287"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80218.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "eca8cadea0f1595ed2c10a0c177b1da9aa9e5269"
          },
          {
            "fixed": "*"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "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.",
  "id": "CVE-2026-80218",
  "modified": "2026-09-20T11:30:50.222997461Z",
  "published": "2026-09-17T13:09:25.585Z",
  "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"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Sign-in token minted for one resource accepted by another in AshAuthentication"
}