Name:Windows Scheduled Task with Suspicious Name id:9e9ab4e3-c9d0-4967-a197-6d755e8a7e6e version:1 date:2025-02-07 author:Steven Dick status:production type:TTP Description:The following analytic detects the creation, modification, or enabling of scheduled tasks with known suspicious or malicious task names. It leverages Windows Security EventCode 4698, 4700, and 4702 to identify when such tasks are registered, modified, or enabled. This activity is significant as it may indicate an attempt to establish persistence or execute malicious commands on a system. If confirmed malicious, this could allow an attacker to maintain access, execute arbitrary code, or escalate privileges, posing a severe threat to the environment. Data_source:
-Windows Event Log Security 4698
-Windows Event Log Security 4700
-Windows Event Log Security 4702
search:`wineventlog_security` EventCode IN (4698,4700,4702) | eval TaskContent = case(isnotnull(TaskContentNew),TaskContentNew,true(),TaskContent) | xmlkv TaskContent | stats count min(_time) as firstTime max(_time) as lastTime latest(Arguments) as Arguments latest(Author) as Author by Computer, TaskName, Command, Enabled, Hidden,Caller_User_Name, EventCode | lookup windows_suspicious_tasks task_name as TaskName | where isnotnull(tool_type) | eval command=TaskName, process=Command+if(isnotnull(Arguments)," ".Arguments,""), src_user=Author, user = Caller_User_Name, dest = Computer | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_scheduled_task_with_suspicious_name_filter`
how_to_implement:To successfully implement this search, you need to be ingesting Windows Security Event Logs with 4698 EventCode enabled. The Windows TA is also required. known_false_positives:False positives are possible if legitimate applications are allowed to register tasks that call a shell to be spawned. Filter as needed based on command-line or processes that are used legitimately. References: -https://attack.mitre.org/techniques/T1053/005/ -https://www.ic3.gov/CSA/2023/231213.pdf -https://news.sophos.com/en-us/2024/11/06/bengal-cat-lovers-in-australia-get-psspsspssd-in-google-driven-gootloader-campaign/ -https://github.com/mthcht/awesome-lists/blob/main/Lists/suspicious_windows_tasks_list.csv drilldown_searches: name:'View the detection results for - "$dest$" and "$user$"' search:'%original_detection_search% | search dest = "$dest$" user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$dest$" and "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$","$user$") 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:'$info_max_time$' name:'Investigate schedule tasks on $dest$' search:'`wineventlog_security` EventCode IN (4698,4700,4702) | xmlkv TaskContent | search dest="$dest$" AND TaskName = "$TaskName$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' tags: analytic_story: - 'Scheduled Tasks' - 'Windows Persistence Techniques' - 'Ransomware' - 'Ryuk Ransomware' asset_type:Endpoint mitre_attack_id: - 'T1053.005' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
