CVE-2025-66629: HedgeDoc is missing state parameter in OAuth2 flows could lead to CSRF

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-12-05 · updated 2026-10-15
Weakness: CWE-352

Description

HedgeDoc is an open source, real-time, collaborative, markdown notes application. Prior to 1.10.4, some of HedgeDoc's OAuth2 endpoints for social login providers such as Google, GitHub, GitLab, Facebook or Dropbox lack CSRF protection, since they don't send a state parameter and verify the response using this parameter. This vulnerability is fixed in 1.10.4.

Affected products

hedgedoc: before 1.10.4 — fixed in 1.10.4

How to fix

Upgrade to a fixed version: hedgedoc 1.10.4. Check the vendor advisory for mitigations.

References

https://github.com/hedgedoc/hedgedoc/commit/35f36fccba941ed8029ee222f7d2a5df17b42e2b
https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-6wm6-3vpq-6qvv

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