Cyber Resilience

CVE-2026-40088

RCE in Praisonai ≤ 4.5.121

Published
09 April 2026
Modified
16 April 2026
Patch / advisory
CVSS Score v3.1 9.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS Score 0.0042 35th percentile
Risk Priority 67 floored blend · peak EPSS

Summary

CVE-2026-40088 is a critical-severity OS Command Injection (CWE-78) vulnerability in Praison Praisonai. Its CVSS base score is 9.6 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 35th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

This vulnerability is AI-related — categorised as AI Agent Protocols and Integrations; in the LLM/Generative AI Risks risk domain.

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-2026-40088 is a command injection vulnerability (CWE-78) in PraisonAI, a multi-agent teams system, affecting versions prior to 4.5.121. The execute_command function and workflow shell execution components are exposed to user-controlled input via agent workflows, YAML definitions, and LLM-generated tool calls. This exposure allows attackers to inject arbitrary shell commands through shell metacharacters.

Unauthenticated remote attackers can exploit the vulnerability over the network with low complexity and no privileges required, though user interaction is needed. By crafting malicious inputs such as workflows or tool calls, attackers can trick users into triggering execution, achieving arbitrary shell command injection on the host system. This results in high impacts to confidentiality, integrity, and availability, with a changed scope, yielding a CVSS v3.1 base score of 9.6.

The vulnerability is addressed in PraisonAI version 4.5.121. The GitHub security advisory (GHSA-2763-cj5r-c79m) and release notes for v4.5.121 detail the fix and recommend upgrading immediately.

This vulnerability has relevance to AI/ML deployments, as it involves LLM-generated tool calls in a multi-agent framework. No public information on real-world exploitation is available.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

PraisonAI is a multi-agent teams system. Prior to 4.5.121, the execute_command function and workflow shell execution are exposed to user-controlled input via agent workflows, YAML definitions, and LLM-generated tool calls, allowing attackers to inject arbitrary shell commands through shell metacharacters.…

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This vulnerability is fixed in 4.5.121.

CWE(s)

AI Security AnalysisAI

AI Category
AI Agent Protocols and Integrations
Risk Domain
LLM/Generative AI Risks
OWASP Top 10 for LLMs 2025
None mapped
AI-specific weaknesses CR
  • CWE-1426 — LLM-generated tool calls reach OS command sink without validation
Mapped by Cyber Resilience · not in NVD. Poisoning and extraction cases are routed to MITRE ATLAS instead of a synthetic CWE.
Classification Reason
Matched keywords: llm

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.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-34935Same product: Praison Praisonai
CVE-2026-34955Same product: Praison Praisonai
CVE-2026-41497Same product: Praison Praisonai
CVE-2026-40113Same product: Praison Praisonai
CVE-2026-44336Same product: Praison Praisonai
CVE-2026-40112Same product: Praison Praisonai
CVE-2026-34953Same product: Praison Praisonai
CVE-2026-40159Same product: Praison Praisonai
CVE-2026-40111Same vendor: Praison
CVE-2026-40116Same product: Praison Praisonai

Affected Assets

praison
praisonai
≤ 4.5.121

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

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.

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).

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.

References