T08 · Insecure Dependencies
Warning
- Location
- SKILL.md:5
- Finding
- Unpinned Third-Party Homebrew Dependency## Vulnerability Details **File Location**: `SKILL.md`, line 5 **Vulnerability Type**: Unpinned third-party package from a mutable external source **Risk Level**: Medium ### Vulnerable Code ```yaml metadata: {"clawdbot":{"emoji":"🧾","requires":{"bins":["summarize"]},"install":[{"id":"brew","kind":"brew","formula":"steipete/tap/summarize","bins":["summarize"],"label":"Install summarize (brew)"}]}} ``` ### Technical Analysis The skill declares installation of the `summarize` executable from the third-party Homebrew tap `steipete/tap`. The dependency is not constrained to a specific version, immutable commit, or cryptographic checksum. Because the project contains only documentation and metadata—not the Homebrew formula or the CLI source—the code ultimately installed and executed cannot be verified from the audited artifact. The effective package may change independently after this skill version has been reviewed. This creates a supply-chain trust boundary in which compromise of the tap, formula, release artifact, or associated maintainer account could cause future installations to retrieve altered code. The CLI's documented purpose includes processing local files and using provider credentials such as `OPENAI_API_KEY`, `ANTHROPIC_API_KEY`, `XAI_API_KEY`, and `GEMINI_API_KEY`. Consequently, a malicious replacement could encounter sensitive file contents or credentials during ordinary use. No evidence establishes that the current upstream package is malicious; the confirmed issue is the mutable and unverified dependency declaration. ### Attack Path 1. An attacker compromises the third-party Homebrew tap, its maintainer account, the referenced formula, or an artifact downloaded by that formula. 2. The attacker modifies the package or release so that installation or execution runs attacker-controlled code. 3. A user or agent installs `steipete/tap/summarize` through the skill's declared installation mechanism. 4. Homebrew resolves the unpinned formula to the ...[truncated 1189 chars]
- Remediation
- ## Remediation Suggestions 1. Pin the dependency to an immutable, audited release rather than relying on the mutable latest formula. 2. Verify downloaded artifacts using a trusted cryptographic checksum or signature. 3. Record the exact package version, source repository revision, and expected digest in the skill metadata or installation workflow. 4. Prefer an official and independently verifiable distribution channel over a third-party tap where one is available. 5. Review the Homebrew formula and all transitive download locations before approving installation. 6. Vendor the audited source or provide a reproducible build process where practical. 7. Run the CLI with least privilege and restrict its filesystem and network access to what the summarization task requires. 8. Provide only the API credential required for the selected provider and avoid exposing unrelated secrets in the process environment. 9. Repeat dependency review whenever the pinned version or verified digest changes.