Name:Detect Remote Access Software Usage DNS id:a16b797d-e309-41bd-8ba0-5067dae2e4be version:4 date:2024-09-30 author:Steven Dick status:production type:Anomaly Description:The following analytic detects DNS queries to domains associated with known remote access software such as AnyDesk, GoToMyPC, LogMeIn, and TeamViewer. This detection is crucial as adversaries often use these tools to maintain access and control over compromised environments. Identifying such behavior is vital for a Security Operations Center (SOC) because unauthorized remote access can lead to data breaches, ransomware attacks, and other severe impacts if these threats are not mitigated promptly. Data_source:
-Sysmon EventID 22
search:| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(DNS.answer) as answer from datamodel=Network_Resolution by DNS.src DNS.query | `drop_dm_object_name("DNS")` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | lookup remote_access_software remote_domain AS query OUTPUT isutility, description as signature, comment_reference as desc, category | eval dest = query | search isutility = True | `remote_access_software_usage_exceptions` | `detect_remote_access_software_usage_dns_filter`
how_to_implement:To implement this search, you must ingest logs that contain the DNS query and the source of the query. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the DNS logs. The logs must also be mapped to the `Network_Resolution` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process. The "exceptions" macro leverages both an Assets and Identities lookup, as well as a KVStore collection called "remote_software_exceptions" that lets you track and maintain device-based exceptions for this set of detections. known_false_positives:It is possible that legitimate remote access software is used within the environment. Ensure that the lookup is reviewed and updated with any additional remote access software that is used within the environment. Known false positives can be added to the remote_access_software_usage_exception.csv lookup to globally suppress these situations across all remote access content References: -https://attack.mitre.org/techniques/T1219/ -https://thedfirreport.com/2022/08/08/bumblebee-roasts-its-way-to-domain-admin/ -https://thedfirreport.com/2022/11/28/emotet-strikes-again-lnk-file-leads-to-domain-wide-ransomware/ drilldown_searches: name:'View the detection results for - "$src$"' search:'%original_detection_search% | search src = "$src$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$src$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$src$") 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: - 'Insider Threat' - 'Command And Control' - 'Ransomware' - 'CISA AA24-241A' asset_type:Endpoint confidence:20 impact:20 message:A domain for a known remote access software $query$ was contacted by $src$. mitre_attack_id: - 'T1219' observable: name:'src' type:'Hostname' - role: - 'Victim' name:'query' type:'Hostname' - role: - 'Attacker' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' required_fields: - '_time' - 'DNS.src' - 'DNS.query' - 'DNS.answer' risk_score:4 security_domain:endpoint manual_test:This detection uses A&I lookups from Enterprise Security.
