T08 · Insecure Dependencies
Warning
- Location
- SKILL.md:77
- Finding
- Unpinned Remote Installation Sources Create Supply-Chain Risk## Vulnerability Details **File Location**: `SKILL.md`, lines 77-81 **Vulnerability Type**: Unpinned third-party package and mutable repository installation **Risk Level**: Medium **Vulnerable Code Snippet**: ```bash # One-click installation using the skills CLI npx skills add zhaoxinghua09-cell/agent-skills -g # Alternatively, clone and copy this skill into the Agent skill directory git clone https://github.com/zhaoxinghua09-cell/agent-skills.git cp -r agent-skills/skills/model-card-generator ~/.workbuddy/skills/ ``` ### Technical Analysis The documented installation process retrieves components from remote, mutable sources without pinning them to reviewed versions or cryptographic identities. The `npx skills` invocation does not specify an exact package version or integrity hash. The Git command clones the repository's current default branch rather than a reviewed commit hash or signed release tag. As a result, the material installed by these commands may differ from the artifact covered by this audit. The copied destination is an Agent skill directory. Content placed there can include instructions and executable scripts that the Agent may subsequently load or invoke. This finding does not establish that the currently audited files are malicious; it identifies a supply-chain path through which future or compromised upstream content could be substituted after review. ### Attack Path 1. An attacker compromises the relevant package publisher, source repository, maintainer account, or upstream distribution channel. 2. The attacker modifies the remote Skill instructions or scripts. 3. A user follows the installation instructions in `SKILL.md`. 4. `npx` obtains an unpinned package, or Git clones the mutable default branch. 5. The retrieved Skill is installed globally or copied into the Agent's Skill directory. 6. The Agent later loads the substituted instructions or executes the substituted scripts under the user' ...[truncated 643 chars]
- Remediation
- ## Remediation Suggestions 1. Pin the CLI package to an exact reviewed version rather than relying on the version selected by `npx`. 2. Pin the Git installation to a specific reviewed commit hash or a cryptographically signed release. 3. Publish and verify SHA-256 checksums or signed provenance attestations for distributed Skill artifacts. 4. Verify the repository identity and fetched commit before copying files into an Agent skill directory. 5. Avoid global installation unless it is operationally necessary; prefer an isolated, least-privileged environment. 6. Document a reproducible installation procedure that guarantees the installed files match the reviewed artifact. 7. Re-audit any fetched version whose digest differs from the approved release digest.
