CVE-2026-39888: PraisonAI is a multi-agent teams system. Prior to 1.5.115, execute_code() in praisonaiagents.tools.python_tools defaults to sandbox_mode="sandbox", which runs…

PriorityP359critical9.9CVSS 3.1

AVNACLPRLUINSCCHIHAH

EPSS

0.54%

41.3th percentile

PraisonAI is a multi-agent teams system. Prior to 1.5.115, execute_code() in praisonaiagents.tools.python_tools defaults to sandbox_mode="sandbox", which runs user code in a subprocess wrapped with a restricted __builtins__ dict and an AST-based blocklist. The AST blocklist embedded inside the subprocess wrapper (blocked_attrs of python_tools.py) contains only 11 attribute names — a strict subset of the 30+ names blocked in the direct-execution path. The four attributes that form a frame-traversal chain out of the sandbox are all absent from the subprocess list (__traceback__, tb_frame, f_back, and f_builtins). Chaining these attributes through a caught exception exposes the real Python builtins dict of the subprocess wrapper frame, from which exec can be retrieved and called under a non-blocked variable name — bypassing every remaining security layer. This vulnerability is fixed in 1.5.115.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
mervinpraison	praisonai	>= 0 < 4.6.40	4.6.40
mervinpraison	praisonaiagents	< 1.5.115	1.5.115
mervinpraison	praisonaiagents	>= 0 < 1.5.115	1.5.115
mervinpraison	praisonaiagents	>= 0 < 1.6.40	1.6.40
praison	praisonai	< 1.5.115	1.5.115

CVSS provenance

nvdv3.19.9CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

ghsa10.0CRITICAL

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