Name:Azure AD User Consent Denied for OAuth Application id:bb093c30-d860-4858-a56e-cd0895d5b49c version:5 date:2024-09-30 author:Mauricio Velazco, Splunk status:production type:TTP Description:The following analytic identifies instances where a user has denied consent to an OAuth application seeking permissions within the Azure AD environment. This detection leverages Azure AD's audit logs, specifically focusing on user consent actions with error code 65004. Monitoring denied consent actions is significant as it can indicate users recognizing potentially suspicious or untrusted applications. If confirmed malicious, this activity could suggest attempts by unauthorized applications to gain access, potentially leading to data breaches or unauthorized actions within the environment. Understanding these denials helps refine security policies and enhance user awareness. Data_source:
-Azure Active Directory Sign-in activity
search:`azure_monitor_aad` operationName="Sign-in activity" properties.status.errorCode=65004 | rename properties.* as * | stats count min(_time) as firstTime max(_time) as lastTime by operationName, user, appDisplayName, status.failureReason | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `azure_ad_user_consent_denied_for_oauth_application_filter`
how_to_implement:You must install the latest version of Splunk Add-on for Microsoft Cloud Services from Splunkbase (https://splunkbase.splunk.com/app/3110/#/details). You must be ingesting Azure Active Directory events into your Splunk environment through an EventHub. This analytic was written to be used with the azure:monitor:aad sourcetype leveraging the SignInLogs log category. known_false_positives:Users may deny consent for legitimate applications by mistake, filter as needed. References: -https://attack.mitre.org/techniques/T1528/ -https://www.microsoft.com/en-us/security/blog/2022/09/22/malicious-oauth-applications-used-to-compromise-email-servers-and-spread-spam/ -https://learn.microsoft.com/en-us/azure/active-directory/manage-apps/protect-against-consent-phishing -https://learn.microsoft.com/en-us/defender-cloud-apps/investigate-risky-oauth -https://www.alteredsecurity.com/post/introduction-to-365-stealer -https://github.com/AlteredSecurity/365-Stealer drilldown_searches: name:'View the detection results for - "$user$"' search:'%original_detection_search% | search user = "$user$"' earliest_offset:'$info_min_time$' latest_offset:'$info_max_time$' name:'View risk events for the last 7 days for - "$user$"' search:'| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") 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: - 'Azure Active Directory Account Takeover' asset_type:Azure Tenant confidence:60 impact:60 message:User $user$ denied consent for an OAuth application. mitre_attack_id: - 'T1528' observable: name:'user' type:'User' - role: - 'Victim' product: - 'Splunk Enterprise' - 'Splunk Enterprise Security' - 'Splunk Cloud' risk_score:36 required_fields: - '_time' - 'operationName' - 'properties.status.errorCode' - 'user' - 'properties.appDisplayName' - 'status.failureReason' security_domain:identity
