T08 · Insecure Dependencies
Warning
- Location
- SKILL.md:20
- Finding
- Unpinned Installation from a Mutable Third-Party Homebrew Tap## Vulnerability Details **File Location**: `SKILL.md`, lines 20–23 **Vulnerability Type**: Unpinned third-party dependency **Risk Level**: Medium ```bash ### Install the CLI ```bash brew install vossenwout/tap/macos-audio-cli ``` ``` ### Technical Analysis The installation instructions require a package from the third-party Homebrew tap `vossenwout/tap` without specifying an immutable version, formula revision, source commit, artifact checksum, or signature. The project contains no vendored formula or executable implementation that would permit independent review of the installed code. As a result, executing this instruction installs whatever formula and package content the external tap serves at that time. The effective code may therefore change after the Skill has been audited. Exploitation requires compromise, malicious modification, or transfer of control of the external tap or its release infrastructure; the audit found no evidence that the named package is currently malicious. ### Attack Path 1. An attacker compromises the third-party Homebrew tap, its maintainer account, or the package release infrastructure. 2. The attacker modifies the formula or referenced artifact to deliver malicious installation or runtime code. 3. A user or agent follows `SKILL.md` and runs: ```bash brew install vossenwout/tap/macos-audio-cli ``` 4. Homebrew retrieves the mutable formula and installs the attacker-controlled package. 5. Malicious code executes during installation or when the installed CLI is subsequently invoked. ### Impact Assessment Successful exploitation could execute code with the privileges of the user running Homebrew or the installed CLI. Within that account's accessible scope, an altered package could read or modify user files, access local audio files passed to the playback command, manipulate Bluetooth and audio state, invoke other available programs, or communicate over the network. No privilege-escalation mechanism is documented in ...[truncated 243 chars]
- Remediation
- ## Remediation Suggestions 1. Pin the CLI to a reviewed, immutable release, formula revision, or source commit rather than relying on the tap's current state. 2. Publish and verify a cryptographic checksum, such as SHA-256, for the expected installation artifact. 3. Document the exact audited version and provide a link to its source code and release provenance. 4. Prefer a trusted package source with signed releases and reproducible build information. 5. Review the Homebrew formula and its transitive dependencies before recommending installation. 6. Require explicit user approval before installing or upgrading dependencies; do not automatically install packages merely because the CLI reports a missing dependency. 7. Periodically re-audit the pinned version and update the recorded checksum only after reviewing the new release.