Name:Windows Unusual Intelliform Storage Registry Access id:99d69078-7dae-4ffe-9f3d-063242772f5a version:1 date:2025-07-16 author:Teoderick Contreras, Splunk status:production type:Anomaly Description:The following analytic identifies processes accessing Intelliform Storage Registry keys used by Internet Explorer. It leverages Windows Security Event logs, specifically monitoring EventCode 4663, which tracks object access events. This activity is significant because it can indicate unauthorized access or manipulation of sensitive registry keys used for storing form data in Internet Explorer. If confirmed malicious, this could lead to data exfiltration, credential theft, or further compromise of the system. Data_source:
-Windows Event Log Security 4663
search:`wineventlog_security` EventCode=4663 NOT (ProcessName IN("C:\\Program Files\\Internet Explorer\\iexplore.exe", "C:\\Windows\\System32\\dllhost.exe", "C:\\Windows\\SysWow64\\dllhost.exe")) ObjectName IN ("*Software\\microsoft\\Internet Explorer\\Intelliforms\\storage2*") | stats count min(_time) as firstTime max(_time) as lastTime by ObjectName ObjectType ProcessName AccessMask process_id EventCode Computer Caller_User_Name | rename Computer as dest Caller_User_Name as user ProcessName as process_name | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_unusual_intelliform_storage_registry_access_filter`
how_to_implement:To successfully implement this search, you must ingest Windows Security Event logs and track event code 4663. For 4663, enable "Audit Object Access" in Group Policy. Then check the two boxes listed for both "Success" and "Failure." known_false_positives:a third party application can access the FileZilla XML config files. Filter is needed. References: -https://stackoverflow.com/questions/1276700/where-does-internet-explorer-stores-its-form-data-history-that-is-uses-for-auto 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: - 'Quasar RAT' asset_type:Endpoint mitre_attack_id: - 'T1552.001' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' security_domain:endpoint
