Name:Windows Vulnerable 3CX Software id:f2cc1584-46ee-485b-b905-977c067f36de version:4 date:2024-09-30 author:Michael Haag, Splunk status:production type:TTP Description:The following analytic detects instances of the 3CXDesktopApp.exe with a FileVersion of 18.12.x, leveraging Sysmon logs. This detection focuses on identifying vulnerable versions 18.12.407 and 18.12.416 of the 3CX desktop app. Monitoring this activity is crucial as these specific versions have known vulnerabilities that could be exploited by attackers. If confirmed malicious, exploitation of this vulnerability could lead to unauthorized access, code execution, or further compromise of the affected system, posing significant security risks. Data_source:
-Sysmon EventID 1
-Windows Event Log Security 4688
-CrowdStrike ProcessRollup2
search:`sysmon` (process_name=3CXDesktopApp.exe OR OriginalFileName=3CXDesktopApp.exe) FileVersion=18.12.* | stats count min(_time) as firstTime max(_time) as lastTime by dest, parent_process_name,process_name, OriginalFileName, CommandLine | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`| `windows_vulnerable_3cx_software_filter`
how_to_implement:To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA. known_false_positives:False positives may be present based on file version, modify the analytic to only look for version between 18.12.407 and 18.12.416 as needed. References: -https://www.sentinelone.com/blog/smoothoperator-ongoing-campaign-trojanizes-3cx-software-in-software-supply-chain-attack/ -https://www.cisa.gov/news-events/alerts/2023/03/30/supply-chain-attack-against-3cxdesktopapp -https://www.reddit.com/r/crowdstrike/comments/125r3uu/20230329_situational_awareness_crowdstrike/ -https://www.3cx.com/community/threads/crowdstrike-endpoint-security-detection-re-3cx-desktop-app.119934/page-2#post-558898 -https://www.3cx.com/community/threads/3cx-desktopapp-security-alert.119951/ drilldown_searches: name:'View the detection results for - "$dest$"' search:'%original_detection_search% | search dest = "$dest$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' tags: analytic_story: - '3CX Supply Chain Attack' asset_type:Endpoint confidence:90 cve: - 'CVE-2023-29059' impact:100 message:A known vulnerable instance of 3CX Software $process_name$ ran on $dest$, related to a supply chain attack. mitre_attack_id: - 'T1195.002' observable: name:'dest' type:'Hostname' - role: - 'Victim' name:'process_name' type:'Process' - role: - 'Attacker' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'OriginalFileName' - 'process_name' - 'EventID' - 'CommandLine' - 'dest' - 'parent_process_name' risk_score:90 security_domain:endpoint
