CVE-2026-40112 Details

A stored cross-site scripting vulnerability has been identified in PraisonAI versions prior to 4.5.128. The issue arises in the Flask API endpoint located in src/praisonai/api.py, where agent output is rendered as HTML without proper sanitization. The vulnerability exists because the _sanitize_html function depends on the nh3 library, which is not listed as a required or optional dependency in pyproject.toml. In default installations, where nh3 is absent, the sanitizer fails to operate effectively, allowing an attacker to inject arbitrary JavaScript that executes in the browser of anyone viewing the API output. This exploitation can occur through RAG data poisoning, web scraping results, or prompt injection.

Users should update to PraisonAI version 4.5.128 or later, and ensure that the nh3 library is installed. Additionally, the dependency management in pyproject.toml should be updated to include nh3 as a required dependency.