name: Linux Sudoers Tmp File Creation id: be254a5c-63e7-11ec-89da-acde48001122 version: 1 date: '2021-12-23' author: Teoderick Contreras, Splunk status: production type: Anomaly description: This analytic is to looks for file creation of sudoers.tmp file cause by editing /etc/sudoers using visudo or editor in linux platform. This technique may abuse by adversaries, malware author and red teamers to gain elevated privilege to targeted or compromised host. /etc/sudoers file controls who can run what commands as what users on what machines and can also control special things such as whether you need a password for particular commands. The file is composed of aliases (basically variables) and user specifications (which control who can run what). data_source: - Sysmon Event ID 11 search: selection1: TargetFilename: '*sudoers.tmp*' condition: selection1 how_to_implement: To successfully implement this search, you need to be ingesting logs with the process name, parent process, and command-line executions from your endpoints. If you are using Sysmon, you can use the Add-on for Linux Sysmon from Splunkbase. known_false_positives: administrator or network operator can execute this command. Please update the filter macros to remove false positives. references: - https://forum.ubuntuusers.de/topic/sudo-visudo-gibt-etc-sudoers-tmp/ tags: analytic_story: - Linux Privilege Escalation - Linux Persistence Techniques asset_type: Endpoint confidence: 90 impact: 80 message: A file $file_name$ is created in $file_path$ on $dest$ mitre_attack_id: - T1548.003 - T1548 observable: - name: dest type: Hostname role: - Victim product: - Splunk Enterprise - Splunk Enterprise Security - Splunk Cloud risk_score: 72 security_domain: endpoint tests: - name: True Positive Test attack_data: - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548.003/sudoers_temp/sysmon_linux.log source: Syslog:Linux-Sysmon/Operational sourcetype: sysmon_linux