Vulnerability Description
PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI's AST-based Python sandbox can be bypassed using type.__getattribute__ trampoline, allowing arbitrary code execution when running untrusted agent code. The _execute_code_direct function in praisonaiagents/tools/python_tools.py uses AST filtering to block dangerous Python attributes like __subclasses__, __globals__, and __bases__. However, the filter only checks ast.Attribute nodes, allowing a bypass. The sandbox relies on AST-based filtering of attribute access but fails to account for dynamic attribute resolution via built-in methods such as type.getattribute, resulting in incomplete enforcement of security restrictions. The string '__subclasses__' is an ast.Constant, not an ast.Attribute, so it is never checked against the blocked list. This vulnerability is fixed in 4.5.128.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Praison | Praisonai | < 4.5.128 |
Related Weaknesses (CWE)
References
- https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-3c4r-6p77-xwExploitVendor Advisory
FAQ
What is CVE-2026-40158?
CVE-2026-40158 is a vulnerability with a CVSS score of 8.6 (HIGH). PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI's AST-based Python sandbox can be bypassed using type.__getattribute__ trampoline, allowing arbitrary code execution when running u...
How severe is CVE-2026-40158?
CVE-2026-40158 has been rated HIGH with a CVSS base score of 8.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-40158?
Check the references section above for vendor advisories and patch information. Affected products include: Praison Praisonai.