critical CVSS 9.8

CVE-2026-40288·Python vulnerability

PraisonAI is a multi-agent teams system. In versions below 4.5.139 of PraisonAI and 1.5.140 of praisonaiagents, the workflow engine is vulnerable to arbitrary command and code execution through untrusted YAML files. When praisonai workflow run <file.yaml> loads a YAML file with type: job, the JobWorkflowExecutor in job_workflow.py processes steps that support run: (shell commands via subprocess.run()), script: (inline Python via exec()), and python: (arbitrary Python script execution)—all without any validation, sandboxing, or user confirmation. The affected code paths include action_run() in workflow.py and _exec_shell(), _exec_inline_python(), and _exec_python_script() in job_workflow.py. An attacker who can supply or influence a workflow YAML file (particularly in CI pipelines, shared repositories, or multi-tenant deployment environments) can achieve full arbitrary command execution on the host system, compromising the machine and any accessible data or credentials. This issue has been fixed in versions 4.5.139 of PraisonAI and 1.5.140 of praisonaiagents.

Severity
critical
Software
Python
Fixed in
1.5.140
Published
2026-04-14

Affected versions

Until: 1.5.140

Fixed in: 1.5.140

How to fix this CVE

Update PraisonAI and praisonaiagents to patched versions 4.5.139 and 1.5.140 respectively to eliminate unsafe YAML workflow execution. These versions introduce input validation and restrict dangerous operations in workflow files. Immediately audit any workflow YAML files in your environment and avoid loading YAML from untrusted sources until patched.

sudo dnf update python3-praisonai python3-praisonaiagents

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'pip show praisonai praisonaiagents' to confirm installed versions are 4.5.139+ and 1.5.140+ respectively
  2. Search for workflow YAML files in your codebase and CI/CD pipelines using 'find . -name "*.yaml" -o -name "*.yml" | xargs grep -l "type: job"'
  3. Review application logs for unexpected subprocess execution patterns or Python exec() calls triggered by workflow runner, particularly lines containing 'JobWorkflowExecutor', 'job_workflow.py', or 'praisonai workflow run'
  4. Verify the patch by checking if /usr/lib/python3*/site-packages/praisonai/job_workflow.py contains input validation on YAML workflow parameters

FAQ

What is CVE-2026-40288?

CVE-2026-40288 is a critical arbitrary code execution flaw in PraisonAI's workflow engine that allows attackers to execute arbitrary shell commands and Python code by crafting malicious YAML workflow files, bypassing all security controls.

Is CVE-2026-40288 being actively exploited?

No, CVE-2026-40288 is not currently listed on CISA's Known Exploited Vulnerabilities catalog, and no public exploits have been disclosed, though the attack vector is straightforward.

What versions of PraisonAI are affected by CVE-2026-40288?

PraisonAI versions before 4.5.139 and praisonaiagents versions before 1.5.140 are vulnerable; all earlier versions lack protections against malicious workflow YAML execution.

How do I check if my server is vulnerable to CVE-2026-40288?

Run 'pip show praisonai praisonaiagents' and compare the Version fields to 4.5.139 and 1.5.140 respectively; if your version is lower, your system is vulnerable.

Does Defensia detect CVE-2026-40288?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If PraisonAI or praisonaiagents is installed on a monitored server, CVE-2026-40288 will appear in your dashboard with remediation steps.

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References

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