CVE-2026-40288

OVERVIEW CVE-2026-40288 is a critical arbitrary command and code execution vulnerability in PraisonAI workflow execution engine affecting versions below 4.5.139 of PraisonAI and 1.5.140 of praisonaiagents. The vulnerability exists in the workflow engine's handling of YAML files, where the JobWorkflowExecutor processes workflow steps without validation, allowing attackers to execute arbitrary shell commands, inline Python code, and external Python scripts through malicious YAML inputs. SEVERITY The vulnerability carries a CVSS 3.1 score of 9.8 CRITICAL with a network-based attack vector requiring no authentication, low complexity, and no user interaction. An attacker can achieve complete compromise of the affected system including confidentiality, integrity, and availability impact. The risk is particularly acute in shared environments such as CI/CD pipelines, collaborative repositories, and multi-tenant deployments where workflow files may be influenced or supplied by untrusted sources. EXPLOITATION STATUS There is currently no active exploitation of this vulnerability detected in the wild, and it is not listed on the CISA Known Exploited Vulnerabilities catalog. The EPSS score of 0.000950000 indicates probability of exploitation remains relatively low compared to historical CVEs. However, given the critical severity and straightforward exploitation mechanism through untrusted YAML files, organizations should prioritize patching to versions 4.5.139 or 1.5.140 or later to prevent future exploitation risk, particularly in environments accepting external workflow submissions.