Cyber Posture

CVE-2026-42435

HighPublic PoC

Published: 05 May 2026

Published
05 May 2026
Modified
05 May 2026
KEV Added
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Patch
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CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0010 26.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Description

OpenClaw versions from 2026.2.22 before 2026.4.12 contain an insufficient shell-wrapper detection vulnerability allowing attackers to inject environment variable assignments at the argv level. Attackers can bypass exec preflight handling to manipulate high-risk shell variables like SHELLOPTS and PS4, affecting execution…

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semantics and security controls.

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match
prevent

Requires timely identification, reporting, and correction of flaws like the shell-wrapper detection bypass via patching to OpenClaw 2026.4.12 or later.

SI-10 Information Input Validation good match
prevent

Enforces validation of argv inputs to prevent injection of environment variable assignments that bypass exec preflight handling.

RA-5 Vulnerability Monitoring and Scanning good match
detect

Mandates vulnerability scanning to identify deployments of vulnerable OpenClaw versions affected by CVE-2026-42435.

Security SummaryAI

CVE-2026-42435 is an insufficient shell-wrapper detection vulnerability affecting OpenClaw versions from 2026.2.22 before 2026.4.12. The flaw enables attackers to inject environment variable assignments at the argv level, bypassing exec preflight handling and allowing manipulation of high-risk shell variables such as SHELLOPTS and PS4. This impacts execution semantics and security controls. The vulnerability carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) and maps to CWE-184.

Attackers with low privileges (PR:L) can exploit this over the network (AV:N) with low attack complexity (AC:L) and no user interaction (UI:N). Exploitation bypasses shell-wrapper protections, enabling manipulation of shell variables to alter execution behavior, achieve high impacts on confidentiality, integrity, and availability (C:H/I:H/A:H), and undermine security controls.

Mitigation is addressed in OpenClaw version 2026.4.12 and later, as evidenced by the fixing commit at https://github.com/openclaw/openclaw/commit/8f8492d172f4c5b4fd7dd9a47855ed620c8770ab. Additional details are provided in the GitHub security advisory at https://github.com/openclaw/openclaw/security/advisories/GHSA-j6c7-3h5x-99g9 and the VulnCheck advisory at https://www.vulncheck.com/advisories/openclaw-shell-wrapper-detection-bypass-via-environment-variable-assignment-injection.

Details

CWE(s)
CWE-184

MITRE ATT&CK Enterprise TechniquesAI

T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
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.
attack.mitre.org →
Why these techniques?

Vulnerability enables direct manipulation of Unix shell variables (SHELLOPTS/PS4) via argv injection to bypass wrapper protections, directly facilitating Unix shell command execution (T1059.004). Low-privilege network exploitation yielding full C/I/A impact maps to exploitation for privilege escalation (T1068). Network-accessible flaw in application service enables exploitation of public-facing application (T1190).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

References