CVE-2026-58489 HedgeDoc: CSRF in GitHub Gist export callback
Attackers can trick logged-in users into exporting private notes to attacker-controlled GitHub Gists via a CSRF vulnerability in the OAuth callback.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-58489?
CVE-2026-58489 is a medium-severity vulnerability in hedgedoc, published on 13 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
HedgeDoc is an open source, real-time collaborative markdown notes application. Prior to 1.11.0, the GitHub Gist export flow created an OAuth2 state value but only checked that it was present rather than validating it against the value expected for the user's session. Because the state was not properly validated, an attacker could forge a callback URL containing their own valid GitHub OAuth code. When processing the callback, HedgeDoc used the victim's logged-in session to select which note to export, but the attacker's authorization code to determine which GitHub account received it. As a result, a logged-in victim who clicked a crafted link could export their own private, protected, or limited note directly into a Gist controlled by the attacker. This issue has been fixed in version 1.11.0.
Weakness: CWE-352
Which versions are affected by CVE-2026-58489?
How do I fix CVE-2026-58489?
No fix has been published for CVE-2026-58489 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-58489 being exploited?
There is no known exploitation of CVE-2026-58489 in the wild and no public exploit code.
Sources
Also known as GHSA-8v9p-5j95-826j.