{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "3.7.2"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "b6d69d072919cbe769234f93d95ed21e1ec129b2"
            }
          ],
          "repo": "https://github.com/laurent22/joplin",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-5px3-4f5x-hjc5"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-290"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55210.json"
  },
  "details": "Joplin is an open source note-taking and to-do application that organises notes and lists into notebooks. Prior to 3.7.2, Joplin Server's UserModel.ssoLogin() returns an existing account matched by an IdP-asserted email without checking the account's is_external flag. In deployments using mixed local and SAML authentication, an attacker whose IdP session can assert a local user's email can pass POST /api/saml, receive a session for that local account, and access or modify the victim's notes, files, and settings without knowing the local password. This issue is fixed in version 3.7.2.",
  "id": "CVE-2026-55210",
  "modified": "2026-09-25T03:30:55.393411537Z",
  "published": "2026-09-21T21:14:31.267Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55210.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/laurent22/joplin/security/advisories/GHSA-5px3-4f5x-hjc5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55210"
    },
    {
      "type": "FIX",
      "url": "https://github.com/laurent22/joplin/commit/b6d69d072919cbe769234f93d95ed21e1ec129b2"
    },
    {
      "type": "FIX",
      "url": "https://github.com/laurent22/joplin/pull/15647"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Joplin: SAML SSO account takeover via email-based account linking (missing is_external check in ssoLogin)"
}