Executive brief
A vulnerability in Gitea, a popular self-hosted Git service, allows a repository administrator to crash the server by providing a non-existent username when tracking time on an issue. This can lead to service outages, excessive log generation, or the disclosure of technical stack traces to the user. The issue is caused by the system failing to stop processing after an error occurs, resulting in a software crash.
Technical details
A NULL pointer dereference (CWE-476) exists in the AddTime API handler within `routers/api/v1/repo/issue_tracked_time.go`. The vulnerability occurs because the code fails to return after an error is encountered in `user_model.GetUserByName()`. If a repository administrator provides a non-existent username in a POST request to `/api/v1/repos/{owner}/{repo}/issues/{index}/times`, the `user` object remains nil, but execution continues to `issues_model.AddTime()`, which dereferences the nil pointer. This triggers a Go runtime panic, potentially leading to a denial of service. The issue is fixed in Gitea version 1.27.0.
Affected products
- Gitea Gitea < 1.27.0
Timeline
- 2026-07-13: disclosed: Initial report by martijnperdaan52
- 2026-07-21: advisory: GitHub Advisory published
- 2026-07-21: patched: Fixed in version 1.27.0
References
- https://api.github.com/users/martijnperdaan52
- https://github.com/martijnperdaan52
- https://api.github.com/users/martijnperdaan52/gists%7B/gist_id%7D
- https://api.github.com/users/martijnperdaan52/repos
- https://avatars.githubusercontent.com/u/268664750?v=4
- https://api.github.com/users/martijnperdaan52/events%7B/privacy%7D