Vulnerability in Laurent22 Joplin
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Laurent22 Joplin — versions < 3.7.2
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-55210?
- CVE-2026-55210 is a high-severity vulnerability in Laurent22 Joplin, classified under Authentication Bypass by Spoofing. CVSS score: 7.4/10. Published 2026-09-21.
- How severe is CVE-2026-55210?
- High severity. CVSS v3 base score is 7.4 out of 10.