T09 · Insecure Skill Coding Practices
Warning
- Location
- SKILL.md:16
- Finding
- Unqualified Git Stash Restoration Can Apply and Remove an Unrelated Stash## Vulnerability Details **File Location**: `SKILL.md`, lines 16-37 **Vulnerability Type**: Unsafe Git state handling **Risk Level**: Medium ### Vulnerable Code ```bash git stash push -m "temp stash before rebase $(date +%Y%m%d%H%M%S)" ``` ```bash git pull --rebase ``` ```bash git stash pop ``` ### Technical Analysis The workflow runs `git stash pop` without verifying that the preceding `git stash push` created a new stash and without identifying the exact stash generated by this invocation. When the working tree has no eligible tracked changes, `git stash push` does not create a new stash entry. If the repository already contains an older stash, the unqualified `git stash pop` operates on the current `stash@{0}`. Consequently, it may apply and remove a pre-existing stash unrelated to the workflow. The sequence also lacks explicit success checks between the state-changing commands. Restoration should not proceed if stashing or `git pull --rebase` fails. Because the Skill is activated by a broad conversational trigger and modifies repository state, the absence of confirmation and state validation increases the likelihood of accidental invocation and repository disruption. ### Attack Path 1. A repository contains a pre-existing stash created by the user or another process. 2. The tracked working tree has no changes eligible for a new stash. 3. The user invokes the Skill through one of its matching work-start phrases. 4. `git stash push` creates no new stash entry. 5. The workflow performs `git pull --rebase`. 6. The unqualified `git stash pop` selects the existing `stash@{0}`. 7. The unrelated stash is applied to the working tree and, if application succeeds, removed from the stash list. ### Impact Assessment The issue does not grant additional operating-system privileges or establish persistence. Its scope is the active Git repository and the files represented by the selected stash. Exploitation ...[truncated 308 chars]
- Remediation
- ## Remediation Suggestions 1. Ask for explicit user confirmation before running repository-mutating Git commands. 2. Validate that the current directory is the intended Git repository and display its root, branch, and remote before proceeding. 3. Capture the stash list or stash object identifier before and after `git stash push` and verify that this invocation created a new entry. 4. Restore only the exact stash created by this workflow. Do not use an unqualified `git stash pop`. 5. Prefer applying the verified stash first and dropping it only after successful application: ```bash before="$(git rev-parse -q --verify refs/stash 2>/dev/null || true)" git stash push -m "temp stash before rebase $(date +%Y%m%d%H%M%S)" || exit 1 after="$(git rev-parse -q --verify refs/stash 2>/dev/null || true)" created_stash="" if [ -n "$after" ] && [ "$after" != "$before" ]; then created_stash="$after" fi git pull --rebase || exit 1 if [ -n "$created_stash" ]; then git stash apply "$created_stash" || exit 1 git stash drop "$created_stash" fi ``` 6. Stop immediately if stashing or rebasing fails. If a rebase conflict occurs, preserve the verified stash and instruct the user to resolve or abort the rebase manually. 7. Clearly report when no new stash was created and skip all restoration commands in that case.