Name:Windows Unsigned DLL Side-Loading id:5a83ce44-8e0f-4786-a775-8249a525c879 version:3 date:2024-09-30 author:Teoderick Contreras, Splunk status:production type:Anomaly Description:The following analytic detects the creation of potentially malicious unsigned DLLs in the c:\windows\system32 or c:\windows\syswow64 folders. It leverages Sysmon EventCode 7 logs to identify unsigned DLLs with unavailable signatures loaded in these critical directories. This activity is significant as it may indicate a DLL hijacking attempt, a technique used by attackers to gain unauthorized access and execute malicious code. If confirmed malicious, this could lead to privilege escalation, allowing the attacker to gain elevated privileges and further compromise the target system. Data_source:
-Sysmon EventID 7
search:`sysmon` EventCode=7 Signed=false OriginalFileName = "-" SignatureStatus="unavailable" ImageLoaded IN ("*:\\windows\\system32\\*", "*:\\windows\\syswow64\\*") | stats count min(_time) as firstTime max(_time) as lastTime by Image ImageLoaded Signed SignatureStatus OriginalFileName process_name dest EventCode ProcessId Hashes IMPHASH | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_unsigned_dll_side_loading_filter`
how_to_implement:To successfully implement this search, you need to be ingesting logs with the process name and imageloaded 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:It is possible some Administrative utilities will load dismcore.dll outside of normal system paths, filter as needed. References: -https://asec.ahnlab.com/en/17692/ -https://www.blackberry.com/us/en/solutions/endpoint-security/ransomware-protection/warzone#:~:text=Warzone%20RAT%20(AKA%20Ave%20Maria)%20is%20a%20remote%20access%20trojan,is%20as%20an%20information%20stealer. 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: - 'Warzone RAT' - 'NjRAT' asset_type:Endpoint confidence:70 impact:70 message:An unsigned dll module was loaded on $dest$ mitre_attack_id: - 'T1574.002' observable: name:'dest' type:'Endpoint' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' risk_score:49 required_fields: - '_time' - 'Image' - 'ImageLoaded' - 'Signed' - 'SignatureStatus' - 'OriginalFileName' - 'process_name' - 'dest' - 'EventCode' - 'ProcessId' - 'Hashes' - 'IMPHASH' security_domain:endpoint
