T03 · Remote Payload Retrieval and Execution
Error
- Location
- SKILL.md:27
- Finding
- Unpinned Remote Installation Script Is Executed Directly## Vulnerability Details **File Location**: `SKILL.md`, line 27 **Vulnerability Type**: Remote payload retrieval and execution **Risk Level**: Critical **Vulnerable Code**: ```bash curl -fsSL https://ollama.ai/install.sh | sh ``` ### Technical Analysis The installation instructions download a mutable script from an external URL and pipe it directly into a shell. The script is executed without version pinning, checksum validation, signature verification, or an opportunity for the user to inspect the downloaded content. Ollama is a documented prerequisite, but dynamically executing its current remote installation script is not necessary for the Skill's runtime functionality and does not follow least-privilege or secure supply-chain practices. Even if the domain is legitimate, the effective payload can change after this Skill has been reviewed. A compromise of the website, hosting infrastructure, DNS resolution, certificate issuance chain, or installation script could convert the documented command into arbitrary local code execution. ### Attack Path 1. An attacker compromises or gains control over the remote installation endpoint or its delivery infrastructure. 2. The attacker modifies the response from `https://ollama.ai/install.sh` to contain malicious shell commands. 3. A user follows the Skill's installation instructions. 4. `curl` retrieves the modified response. 5. The pipe sends the response directly to `sh`, which executes it without verification. 6. The payload performs arbitrary actions under the invoking user's account and may seek elevated privileges if the installer invokes or requests `sudo`. ### Impact Assessment Successful exploitation permits arbitrary command execution with the privileges of the user following the installation instructions. The payload could read or modify user data, steal credentials accessible to that account, install persistence, download additional payloads, or alter development a ...[truncated 146 chars]
- Remediation
- ## Remediation Suggestions - Remove the `curl | sh` pipeline from the installation instructions. - Prefer a trusted operating-system package manager with a pinned package version. - If a standalone installer is required, download a versioned artifact to disk before executing it. - Publish and verify a cryptographic signature from a trusted publisher key and a pinned SHA-256 or stronger checksum. - Let the user inspect the downloaded artifact before execution. - Clearly document whether elevated privileges are required and avoid invoking the installer as `root` unless strictly necessary. - Pin the download to an immutable release rather than a mutable installation endpoint.
