The Gitea web handlers for adding and removing reactions on issues and comments did not refuse locked issues for users without write access, although the API did. A signed-in user who could read an issue could therefore add or remove reactions on a locked issue and its comments, bypassing the interaction restriction of the lock. Only reactions were affected; no content could be changed.
https://github.com/go-gitea/gitea/security/advisories/GHSA-wx44-9m3m-rjqx
https://github.com/go-gitea/gitea/releases/tag/v28.2.0
https://github.com/go-gitea/gitea/pull/39847
https://github.com/go-gitea/gitea/pull/39839