T08 · Insecure Dependencies
Warning
- Location
- SKILL.md:27
- Finding
- Unpinned Remote Global Installation Creates a Supply-Chain Execution Risk<![CDATA[ ## Vulnerability Details **File Location**: `SKILL.md:27` and `SKILL.md:83` **Vulnerability Type**: Unpinned remote dependency installation **Risk Level**: Medium ### Vulnerable Code ```bash npx skills add heredotnow/skill --skill here-now -g ``` The same command is presented both as the recommended installation method and as the fallback when bundled scripts are unavailable. ### Technical Analysis The installation command retrieves and installs a mutable remote Skill revision without pinning the `skills` CLI or the requested Skill to an immutable version, commit, or verified artifact digest. The `-g` option also installs the retrieved content globally. Consequently, the code that executes during or after installation may differ from the artifact reviewed in this audit. A compromise of the package publisher, upstream repository, package registry, or dependency resolution process could introduce arbitrary code into a command users are explicitly instructed to run. This is a supply-chain weakness rather than evidence that the currently reviewed scripts contain a hidden payload. Nevertheless, the recommended installation process crosses the trust boundary from audited local content to mutable remote content. ### Attack Path 1. An attacker compromises the upstream package, repository, publisher account, or dependency-distribution channel. 2. The attacker publishes a modified version under the same mutable package or Skill identifier. 3. A user or Agent follows the documented `npx skills add ... -g` instruction. 4. The package manager retrieves and runs the attacker-controlled revision. 5. The malicious revision executes with the invoking user's permissions and is installed globally. ### Impact Assessment Successful exploitation can result in arbitrary code execution under the invoking account. Depending on that account's permissions, the payload could access local files, Agent credentials, environment variables, project data, and network resou ...[truncated 121 chars]
- Remediation
- <![CDATA[ ## Remediation Suggestions 1. Pin the `skills` CLI to a reviewed, exact version rather than allowing `npx` to resolve a mutable latest release. 2. Pin the Skill to an immutable release, commit hash, or content digest. 3. Verify downloaded artifacts with a cryptographic checksum or signature before installation. 4. Prefer project-local installation over global installation unless global scope is explicitly required. 5. Use package-manager lockfiles where applicable and document the expected artifact digest. 6. Perform installation with the least-privileged account available and avoid lifecycle-script execution where the tooling supports that restriction. ]]>
