T08 · Insecure Dependencies
Warning
- Location
- SKILL.md:525
- Finding
- Mutable and Unverified Remote Skill-Pack Installation## Vulnerability Details **File Location**: `SKILL.md`, lines 525-532 **Vulnerability Type**: Supply-chain risk from an unpinned remote dependency **Risk Level**: Medium ### Vulnerable Code ```bash # Clone the complete Bolta skills repository git clone https://github.com/boltaai/bolta-skills.git # Or download the latest release curl -L https://github.com/boltaai/bolta-skills/archive/refs/heads/main.zip -o bolta-skills.zip unzip bolta-skills.zip ``` ### Technical Analysis Both installation methods retrieve content from the mutable default branch of an external repository. Neither method pins the downloaded content to an immutable commit or release, and no checksum or cryptographic signature is verified before extraction. Although the ZIP archive is not directly executed by these commands, it contains instruction-bearing skills intended to be loaded by an AI agent. Consequently, changes made to the remote branch after this audit can alter the effective behavior of the installed skill pack without changing the audited `SKILL.md`. Recommending installation of the complete repository also expands the trust boundary from this documentation-only registry to more than 36 externally maintained skills. This exceeds the minimum dependency footprint needed merely to provide registry and recommendation functionality. ### Attack Path 1. An attacker compromises the upstream repository, a maintainer account, or the branch publication process. 2. The attacker adds malicious or unsafe instructions to one or more skills on the `main` branch. 3. A user follows the documented `git clone` or `curl` installation command. 4. The mutable, attacker-controlled content is downloaded without integrity verification. 5. The user or agent loads one of the downloaded skills. 6. The malicious instructions may then attempt to use whatever tools, credentials, network access, or workspace permissions are available to that agent. ### Impact Ass ...[truncated 929 chars]
- Remediation
- ## Remediation Suggestions 1. Replace references to `main` with an immutable, reviewed commit hash or a specific release tag. 2. Publish a SHA-256 digest for every supported archive and verify it before extraction: ```bash curl -L https://github.com/boltaai/bolta-skills/archive/<immutable-commit>.zip -o bolta-skills.zip echo "<expected-sha256> bolta-skills.zip" | sha256sum --check - unzip bolta-skills.zip ``` 3. Prefer signed release artifacts and verify the maintainer's cryptographic signature before installation. 4. Recommend downloading only the individual skills required for the selected workflow rather than installing the full repository. 5. Require local review or automated security scanning of every downloaded `SKILL.md` and associated script before making it available to an agent. 6. Load newly installed skills in a sandbox with no secrets and minimal tool permissions until their behavior has been verified. 7. Document the exact reviewed version in both the registry metadata and installation instructions, and fail closed if that version cannot be retrieved or verified.
