Name:Zscaler Adware Activities Threat Blocked id:3407b250-345a-4d71-80db-c91e555a3ece version:3 date:2024-09-30 author:Gowthamaraj Rajendran, Splunk status:production type:Anomaly Description:The following analytic identifies potential adware activity blocked by Zscaler. It leverages web proxy logs to detect blocked actions associated with adware threats. Key data points such as device owner, user, URL category, destination URL, and IP are analyzed. This activity is significant as adware can degrade system performance, lead to unwanted advertisements, and potentially expose users to further malicious content. If confirmed malicious, it could indicate an attempt to compromise user systems, necessitating further investigation and remediation to prevent potential data breaches or system exploitation. Data_source:
search:`zscaler_proxy` action=blocked threatname=*adware* | stats count min(_time) as firstTime max(_time) as lastTime by action deviceowner user urlcategory url src dest | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `zscaler_adware_activities_threat_blocked_filter`
how_to_implement:You must install the latest version of Zscaler Add-on from Splunkbase. You must be ingesting Zscaler events into your Splunk environment through an ingester. This analytic was written to be used with the "zscalernss-web" sourcetype leveraging the Zscaler proxy data. This enables the integration with Splunk Enterprise Security. Security teams are encouraged to adjust the detection parameters, ensuring the detection is tailored to their specific environment. known_false_positives:False positives are limited to Zscaler configuration. References: -https://help.zscaler.com/zia/nss-feed-output-format-web-logs drilldown_searches: name:'View the detection results for - "$src$" and "$user$"' search:'%original_detection_search% | search src = "$src$" user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$src$" and "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$src$", "$user$") 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:'$info_max_time$' tags: analytic_story: - 'Zscaler Browser Proxy Threats' asset_type:Web Server confidence:80 impact:10 message:Potential Adware Activity blocked from dest -[$dest$] on $src$ for user-[$user$]. mitre_attack_id: - 'T1566' observable: name:'src' type:'IP Address' - role: - 'Victim' name:'user' type:'User' - role: - 'Victim' name:'url' type:'URL String' - role: - 'Attacker' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' risk_score:8 required_fields: - 'action' - 'threatname' - 'deviceowner' - 'user' - 'urlcategory' - 'url' - 'dest' - 'dest_ip' - 'action' security_domain:threat
