{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-55210", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-16T16:16:32.627Z", "datePublished": "2026-09-21T21:14:31.267Z", "dateUpdated": "2026-09-21T21:14:31.267Z"}, "containers": {"cna": {"title": "Joplin: SAML SSO account takeover via email-based account linking (missing is_external check in ssoLogin)", "problemTypes": [{"descriptions": [{"cweId": "CWE-290", "lang": "en", "description": "CWE-290: Authentication Bypass by Spoofing", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.4, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/laurent22/joplin/security/advisories/GHSA-5px3-4f5x-hjc5", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/laurent22/joplin/security/advisories/GHSA-5px3-4f5x-hjc5"}, {"name": "https://github.com/laurent22/joplin/pull/15647", "tags": ["x_refsource_MISC"], "url": "https://github.com/laurent22/joplin/pull/15647"}, {"name": "https://github.com/laurent22/joplin/commit/b6d69d072919cbe769234f93d95ed21e1ec129b2", "tags": ["x_refsource_MISC"], "url": "https://github.com/laurent22/joplin/commit/b6d69d072919cbe769234f93d95ed21e1ec129b2"}], "affected": [{"vendor": "laurent22", "product": "joplin", "versions": [{"version": "< 3.7.2", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-21T21:14:31.267Z"}, "descriptions": [{"lang": "en", "value": "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."}], "source": {"advisory": "GHSA-5px3-4f5x-hjc5", "discovery": "UNKNOWN"}}}}