An authenticated user of any role could inject arguments into git
subprocesses running as the backend user (root under systemd):
- repo_url was passed unvalidated to git ls-remote/clone, enabling the
ext:: transport (host command execution on git < 2.52 defaults) and
file:// local-repository disclosure (all git versions).
- app_path on POST /deploy/clone was passed without a '--' terminator,
enabling --upload-pack=<cmd> option injection independent of git
version and protocol.*.allow policy.
- branch flowed into 'git fetch origin <branch>' as an unterminated
refspec.
Fix (new app/utils/git_security.py applied at every affected sink):
- repo_url scheme allowlist (https/http/git/ssh + scp-like SSH);
rejects ext::/file://, local paths, leading '-', whitespace.
- '-c protocol.ext.allow=never -c protocol.file.allow=never' pinned on
every remote-touching git call, plus a restrictive GIT_ALLOW_PROTOCOL
in the subprocess environment.
- '--' positional terminator before URL/path/refspec arguments —
co-load-bearing with protocol pinning, which alone does not stop
option injection such as --upload-pack=<cmd>.
- branch/ref validation (leading '-', ref-format metacharacters) for
clone --branch, fetch refspecs and stored deploy configs.
- POST /deploy/clone now confines app_path to the managed apps root,
mirroring how /apps/from-repository derives it server-side.
Adds 31 regression tests; bumps version to 1.7.86.
Reported-by: CaptBoykin
Co-authored-by: Tyler Boykin <25166954+CaptBoykin@users.noreply.github.com>
