Gogs: RCE via git rebase --exec argument injection in pull request merge

Gogs is an open source self-hosted Git service. Prior to 0.14.3, Gogs allows authenticated users to achieve Remote Code Execution (RCE) on the server by creating a pull request with a specially crafted branch name that injects the --exec flag into the git rebase command during the "Rebase before merging" merge operation. This vulnerability is fixed in 0.14.3.