CVE-2026-46649 Joplin: SSO Auth Code Login Missing Rate Limiting — 9-Digit Numeric Code Brute-Forceable via Unprotected Endpoint
An unauthenticated attacker can brute-force SSO login codes to take over user accounts and modify their notes and settings.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-46649?
CVE-2026-46649 is a critical authentication bypass vulnerability in laurent22 joplin, published on 21 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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 GET /api/login_with_code/:id endpoint accepts a nine-digit SSO authentication code with a ten-minute lifetime without applying limiterLoginBruteForce. An unauthenticated attacker who targets a user during an active SSO login can make unlimited guesses, and a correct code returns a full session token that permits access to and modification of the user's notes, notebooks, and account settings. This issue is fixed in version 3.7.2.
Weakness: CWE-307
Which versions are affected by CVE-2026-46649?
How do I fix CVE-2026-46649?
No fix has been published for CVE-2026-46649 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-46649 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-46649 exists.
Sources
Also known as GHSA-6vwc-4hrg-qp5h.