T03 · Remote Payload Retrieval and Execution
Error
- Location
- README.md:18
- Finding
- Unverified Remote Installation Script Executed from a Mutable Branch## Vulnerability Details **File Location**: `README.md:18-19` **Vulnerability Type**: Remote payload retrieval and execution **Risk Level**: Critical **Vulnerable Code**: ```bash curl -fsSL https://raw.githubusercontent.com/Wray151/xeontts/main/install.sh \ | REPO_URL=https://github.com/Wray151/xeontts bash ``` ### Technical Analysis The documented installation command retrieves a shell script from the mutable `main` branch of a personal GitHub repository and passes the response directly to `bash`. It does not pin a reviewed commit, verify a cryptographic checksum, validate a signature, or provide an inspection boundary before execution. Consequently, the effective installer can change after this version of the Skill has been audited. Compromise of the repository, maintainer account, release process, or an authorized but malicious update could turn the documented command into an arbitrary code-execution channel. This behavior exceeds the minimum privileges required for local text-to-speech operation. Downloading model data and dependencies is relevant to the declared function, but executing an unverified, mutable remote shell program is not necessary. ### Attack Path 1. An attacker compromises the `Wray151/xeontts` repository, its maintainer account, or another mechanism capable of changing `main/install.sh`. 2. The attacker replaces or modifies the remote installer with commands that steal files, alter the environment, establish persistence, or download additional payloads. 3. A user or AI agent follows the README and executes the pipe-to-shell command. 4. `curl` retrieves the attacker-controlled version without committing it to a reviewable local file. 5. `bash` immediately executes the response with the privileges of the invoking user. 6. Because the legitimate installer is expected to invoke `sudo apt-get`, a malicious replacement could also request elevated execution in a context where users expect a privilege ...[truncated 579 chars]
- Remediation
- ## Remediation Suggestions 1. Remove the `curl | bash` installation method from the README and installer comments. 2. Require users to clone or download a specific reviewed commit rather than the mutable `main` branch. 3. Publish release artifacts with SHA-256 checksums and preferably cryptographic signatures. 4. Download the installer to a local file, verify its checksum or signature, and permit inspection before execution. 5. Separate privileged system-package installation from the project installer. Document `sudo apt-get install -y espeak-ng` as an explicit user-controlled prerequisite. 6. Use a command resembling the following pattern: ```bash git clone https://github.com/Wray151/xeontts.git cd xeontts git checkout <reviewed-commit-hash> sha256sum -c install.sh.sha256 bash install.sh ``` 7. Protect repository releases through branch protection, mandatory review, signed commits or tags, and multi-factor authentication.