Cyber Resilience

CVE-2026-40288

RCE in Praisonai ≤ 4.5.139

Published
14 April 2026
Modified
20 April 2026
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0061 46th percentile
Risk Priority 72 floored blend · peak EPSS

Summary

CVE-2026-40288 is a critical-severity OS Command Injection (CWE-78) vulnerability in Praison Praisonai. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 46th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-40288 is a critical vulnerability in the workflow engine of PraisonAI, a multi-agent teams system, affecting versions below 4.5.139, as well as the praisonaiagents package in versions below 1.5.140. The flaw enables arbitrary command and code execution through untrusted YAML files processed by the JobWorkflowExecutor in job_workflow.py. Specifically, when a YAML file with type: job is loaded via the praisonai workflow run command, steps supporting run (shell commands executed via subprocess.run()), script (inline Python via exec()), and python (arbitrary Python scripts) are processed without validation, sandboxing, or user confirmation. 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—such as in CI pipelines, shared repositories, or multi-tenant deployment environments—can exploit this to achieve full arbitrary command execution on the host system. This compromises the machine, accessible data, and credentials, with a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), linked to CWE-78 (OS Command Injection) and CWE-94 (Code Injection).

The GitHub security advisory at https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-vc46-vw85-3wvm confirms the issue has been addressed in PraisonAI version 4.5.139 and praisonaiagents version 1.5.140, recommending immediate upgrades to mitigate the risk.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1059.002 AppleScript Execution
Adversaries may abuse AppleScript for execution.
T1059.005 Visual Basic Execution
Adversaries may abuse Visual Basic (VB) for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-40287Same product: Praison Praisonai
CVE-2026-39891Same product: Praison Praisonai
CVE-2026-44334Same product: Praison Praisonai
CVE-2026-40156Same product: Praison Praisonai
CVE-2026-40158Same product: Praison Praisonai
CVE-2026-44336Same product: Praison Praisonai
CVE-2025-1976Shared CWE-78, CWE-94
CVE-2024-41468Shared CWE-78, CWE-94
CVE-2024-6507Shared CWE-78, CWE-94
CVE-2022-45699Shared CWE-78, CWE-94

Affected Assets

praison
praisonai
≤ 4.5.139
praison
praisonaiagents
≤ 1.5.140

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5
  • V1.3.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect command sanitization during development.

Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.

Least privilege reduces the permissions available to any process that could be subverted by injected commands.

Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.

Requiring documented secure development standards and tools enforces use of safe code-generation APIs and escaping.

Secure engineering principles require proper neutralization of untrusted input before command construction.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

PR.DS-10 none match
prevents

PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

prevents

Banning unapproved code samples and unauthenticated web services, combined with secure-coding standards and SAST, prevents the dynamic generation or inclusion of attacker-supplied code.

none

Controls that restrict unauthorized or malicious code from being introduced via external networks or removable media limit opportunities for an attacker to inject and execute arbitrary code.

References