T08 · Insecure Dependencies
Warning
- Location
- SKILL.md:10
- Finding
- Unpinned Third-Party Homebrew Dependency## Vulnerability Details **File Location**: `SKILL.md`, lines 10–18 **Vulnerability Type**: Supply-chain risk from an unpinned third-party package source **Risk Level**: Medium ### Vulnerable Code Snippet ```yaml "install": [ { "id": "brew", "kind": "brew", "formula": "steipete/tap/sag", "bins": ["sag"], "label": "Install sag (brew)", }, ], ``` ### Technical Analysis The skill directs users to install `sag` from the third-party Homebrew tap `steipete/tap` without specifying a fixed version, immutable artifact digest, or checksum. The dependency's implementation is not included in the reviewed project, so its installation logic and executable behavior cannot be audited from this package. Because the formula is mutable, a compromise of the tap, its maintainer account, release infrastructure, or referenced artifacts could cause future installations to retrieve attacker-controlled code without any change to this skill. This is a supply-chain exposure rather than evidence that the current dependency is malicious. ### Attack Path 1. An attacker compromises the third-party Homebrew tap, maintainer credentials, release infrastructure, or an artifact referenced by the formula. 2. The attacker modifies the formula or release artifact to include malicious installation or runtime behavior. 3. A user installs the skill dependency through the declared `steipete/tap/sag` formula. 4. Homebrew downloads and executes or installs the attacker-controlled content under the installing user's privileges. 5. The malicious `sag` executable can subsequently run whenever the skill invokes it. 6. If `ELEVENLABS_API_KEY` or `SAG_API_KEY` is present in the executable's environment, the malicious program may read and exfiltrate it. ### Impact Assessment Successful exploitation could provide arbitrary code execution with the privileges of the user installing or invoking the dependency. Th ...[truncated 493 chars]
- Remediation
- ## Remediation Suggestions 1. Prefer a verified official package source whose ownership and release process can be independently validated. 2. Pin the dependency to a specific audited version rather than implicitly accepting the latest formula revision. 3. Verify downloaded artifacts with a cryptographic SHA-256 checksum or a trusted signature before installation. 4. Record the expected formula revision, source repository, release artifact, and checksum in the skill metadata or installation documentation. 5. Use automated dependency monitoring to detect formula ownership changes, checksum changes, compromised releases, and newly disclosed vulnerabilities. 6. Run the TTS executable with least privilege and expose only the environment variables and filesystem paths required for operation. 7. Store the ElevenLabs API key in an appropriate secret manager, restrict its account permissions and quota where supported, and rotate it if dependency compromise is suspected. 8. Consider vendoring or reproducibly building a reviewed version of the dependency when the platform supports secure, immutable distribution.