Dokku is a docker-powered PaaS. Prior to 0.38.2, the app name validation regex (^[a-z0-9][^/:_A-Z]*$) permits shell metacharacters. When an authenticated user pushes to a git remote with a crafted app name, the name is embedded unquoted into a bash pre-receive hook script via an unquoted heredoc (<<EOF instead of <<'EOF') in fn-git-create-hook() at plugins/git/internal-functions:378. On git push, bash interprets the semicolon as a command separator, executing arbitrary commands as the dokku user. This vulnerability is fixed in 0.38.2.