compose-lint: File paths embedded in pull requests can inject CI workflow commands through command-line error messages 

Impact

0.31.0 fixed GHSA-6f4g-xm8v-pgv6, where text from a Compose file became GitHub Actions workflow commands in compose-lint's output. The fix escapes the command openers in compose-lint's own output, but not in the argument parser's error messages. When a repository path reaches compose-lint's arguments without a -- before it, the argument parser prints it raw in its error message. That includes a carriage return, which the runner treats as a line break, so a command can also start a new line there.

A pull request can therefore create annotations, fold or hide parts of the job log, or issue other commands the runner accepts, when CI runs compose-lint over it, before anyone reviews it. The pass/fail result is not changed.

Affected setups pass repository paths to compose-lint without a -- before them: the pre-commit hook when args: is set without the documented trailing --, or the compose-lint package or Docker image called that way in a workflow. The pre-commit hook's default configuration passes -- and is not affected. The GitHub Action turns command processing off around each compose-lint run, so it is not affected.

Found during an internal pre-1.0 security review. It was first published as part of GHSA-r7j4-crjv-h467, together with four other gaps in the same fix. Each gap now has its own advisory.

Docker image. composelint/compose-lint tag 0.31.0 and the matching minor tag are affected, as was latest while it pointed to 0.31.0.

Releases before 0.31.0 are covered by GHSA-6f4g-xm8v-pgv6.

Patches

Fixed in 0.32.0. The argument parser's messages go through the same sanitizer as the rest of compose-lint's output.

Workarounds

• Upgrade to 0.32.0 or later.
• End the pre-commit hook's args: with --, and put -- before file paths when calling compose-lint directly.
• On GitHub Actions, use the tmatens/compose-lint Action, or bracket the compose-lint step with ::stop-commands::<random token> and ::<token>::, as the Action does.

Reproduction

On compose-lint 0.31.0 on a GitHub-hosted runner (runner 2.337.0), compose-lint '--##[warning]X/compose.yml' with no -- creates an annotation. The same path after -- creates none. The composelint/compose-lint:0.31.0 image produces byte-identical output to the package.