v1.8.4

OpenSignLabs/OpenSignv1.8.4Apr 9, 2026by lfnovo

AI Summary

Critical security release addressing vulnerabilities for Remote Code Execution, arbitrary file writes, and arbitrary file reads reported by CERT-EU.

Key Highlights

Bumped ai-prompter to 0.4.0 to use `SandboxedEnvironment` for Jinja2 templates.
Fixed arbitrary file write via path traversal using `os.path.basename()` and path validation.
Fixed arbitrary file read via Local File Inclusion by validating paths against the uploads directory.

New Features

Security hardening via sandboxed template rendering
Path sanitization for file uploads
Path validation for file reading

Full Release Notes

## Security

Three vulnerabilities reported by CERT-EU Offensive Security Team via coordinated disclosure:

- **Remote Code Execution via Server-Side Template Injection** (CVSS 9.2 Critical)
  - User-created transformation prompts were rendered by an unsandboxed Jinja2 environment, allowing arbitrary Python code execution on the server. Bumped ai-prompter to 0.4.0 which uses `SandboxedEnvironment` for all template rendering.

- **Arbitrary file write via path traversal** (CVSS 7.0 High)
  - File upload did not sanitize filenames, allowing path traversal payloads (e.g., `../../../../tmp/test.txt`) to write files outside the upload directory. Filenames are now sanitized with `os.path.basename()` and resolved paths are validated.

- **Arbitrary file read via Local File Inclusion** (CVSS 8.2 High)
  - The source creation endpoint accepted arbitrary `file_path` values, allowing reading of any file on the container (e.g., `/etc/passwd`, `/proc/self/environ`). File paths are now validated to be within the uploads directory.

### Affected versions

All versions up to and including v1.8.3.

### Recommended action

Upgrade to v1.8.4 immediately.

### Credit

Reported by [CERT-EU](https://cert.europa.eu) Offensive Security Team via coordinated vulnerability disclosure.