CVE-2026-55210

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.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/laurent22/joplin/commit/b6d69d072919cbe769234f93d95ed21e1ec129b2
https://github.com/laurent22/joplin/pull/15647
https://github.com/laurent22/joplin/security/advisories/GHSA-5px3-4f5x-hjc5

Configurations

No configuration.

History

21 Sep 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-21 22:16

Updated : 2026-09-23 18:30

NVD link : CVE-2026-55210

Mitre link : CVE-2026-55210

CVE.ORG link : CVE-2026-55210

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

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