CVE-2026-28795

Impact

The save_report tool in openchatbi/tool/save_report.py suffers from a critical path traversal vulnerability due to insufficient input sanitization of the file_format parameter. 

The function only removes leading dots of file_format using file_format.lstrip(".") but allows path traversal sequences like /../../ to pass through unchanged. When the filename is constructed via string concatenation in 

    f"{timestamp}{cleantitle}.{file_format}"

malicious path sequences are preserved, enabling attackers to write files outside the designated report directory. 

An attacker can manipulate the LLM to call the tool with a specific file_format to overwrite critical system files like init.py, potentially leading to remote code execution.

​

Patches

• Affected versions:

<=0.2.1

• Patched versions:

0.2.2 (includes fix from PR #12: https://github.com/zhongyu09/openchatbi/pull/12)

Workarounds

No

References

• Issue #10: https://github.com/zhongyu09/openchatbi/issues/10
• PR #12: https://github.com/zhongyu09/openchatbi/pull/12