T03 · Remote Payload Retrieval and Execution
Error
- Location
- README_EN.md:45
- Finding
- Unverified Remote Script Executed with Root Privileges<![CDATA[ ## Vulnerability Details **File Location**: `README_EN.md:45` and equivalent instruction in `README.md:45` **Vulnerability Type**: Remote payload retrieval and execution **Risk Level**: Critical ### Vulnerable Code ```bash curl -fsSL https://deb.nodesource.com/setup_lts.x | sudo -E bash - && sudo apt-get install -y nodejs ``` ### Technical Analysis The installation instructions retrieve a mutable script from an external server and pass it directly to a privileged Bash process. The script is neither pinned to an immutable version nor verified through a cryptographic hash or signature. Consequently, the code that ultimately executes can change after the Skill package has been reviewed. The pipeline also prevents users from inspecting the downloaded script before execution. Although the URL belongs to a recognizable Node.js package provider, that does not remove the risks associated with compromise of the hosting infrastructure, DNS resolution, TLS trust chain, or upstream account. This behavior exceeds least privilege because installing Node.js for an optional web-conversion feature does not require executing an unreviewed remote script directly as root. ### Attack Path 1. A user follows the Linux installation instructions. 2. `curl` retrieves the current contents of `setup_lts.x`. 3. The retrieved bytes are passed directly to `sudo -E bash`. 4. If the remote endpoint, delivery path, or signing account has been compromised, attacker-controlled shell commands execute with root privileges. 5. Those commands can modify system files, install packages or services, access root-readable data, and establish persistence. ### Impact Assessment Successful exploitation provides arbitrary operating-system command execution as root. The affected scope includes the entire host rather than only the project directory. An attacker could alter system packages and configuration, read protected files, create privileged accounts, install persistence mechanisms, or c ...[truncated 64 chars]
- Remediation
- <![CDATA[ ## Remediation Suggestions 1. Remove the `curl | sudo bash` pipeline. 2. Prefer the operating system's standard, signed package repositories where feasible. 3. If NodeSource is necessary: - Download a version-pinned installer or repository configuration file to disk. - Verify its publisher signature and a checksum obtained through a separate trusted channel. - Display or inspect the file before execution. - Require explicit user confirmation before any privileged operation. 4. Do not preserve the caller's complete environment with `sudo -E` unless specific variables are demonstrably required. 5. Clearly identify Node.js as optional and avoid requesting administrator privileges unless the user selects the corresponding feature. 6. Apply the same correction to both `README.md` and `README_EN.md`. ]]>