T03 · Remote Payload Retrieval and Execution
Error
- Location
- SKILL.md:63
- Finding
- Unverified Remote Installer Downloaded and Executed Directly<![CDATA[ ## Vulnerability Details **File Location**: `SKILL.md`, lines 63–67 **Vulnerability Type**: Remote payload retrieval and execution **Risk Level**: High ### Vulnerable Code ```bash curl -fsSL https://cli.oomol.com/install.sh | bash # macOS / Linux ``` ```powershell irm https://cli.oomol.com/install.ps1 | iex # Windows PowerShell ``` ### Technical Analysis The installation instructions retrieve mutable content from an external server and pass it directly to a command interpreter. The Bash command pipes the HTTP response into `bash`, while the PowerShell command evaluates it through `iex` (`Invoke-Expression`). Neither installation path pins a release version, verifies a cryptographic checksum, validates a publisher signature, nor gives the user an opportunity to inspect the downloaded file before execution. Consequently, the effective code executed by these instructions can change after the Skill has been reviewed. Although installing the `oo` CLI is related to the Skill's declared purpose, immediate execution of an unverified network response is not the minimum privilege or safest mechanism required for setup. A conventional, versioned package installation or a download-verify-execute process would provide the same functionality with less supply-chain exposure. ### Attack Path 1. The `oo` command is unavailable, causing the user or Agent to follow the documented first-time setup instructions. 2. The system requests `install.sh` or `install.ps1` from `cli.oomol.com`. 3. An attacker compromises the hosting infrastructure, installer publishing process, DNS resolution, or another relevant delivery-chain component. 4. The server returns attacker-controlled shell or PowerShell code. 5. The pipe or `Invoke-Expression` evaluates the response immediately without integrity or authenticity verification. 6. The payload executes with the privileges of the user running the installation command. ### Impact Assessment Successful exploitation p ...[truncated 885 chars]
- Remediation
- <![CDATA[ ## Remediation Suggestions 1. Remove all instructions that pipe downloaded content directly into a shell or evaluate it with `Invoke-Expression`. 2. Direct users to a versioned release artifact or an established platform package manager. 3. Pin the installer or package to a specific reviewed version rather than a mutable latest-release URL. 4. Publish a SHA-256 or stronger cryptographic digest through a separately protected channel and require verification before execution. 5. Where supported, sign release artifacts and require validation against a documented publisher key or operating-system trust mechanism. 6. Use an explicit staged process, for example: - Download the installer to a local file. - Verify its signature and checksum. - Allow inspection of the file. - Execute it only after successful verification. 7. Document the permissions needed by the installer and advise users not to run it with administrative or root privileges unless a specific, justified installation step requires them. 8. Prefer package-manager examples that preserve provenance, versioning, integrity verification, and upgrade accountability. ]]>