Query: rule covering Detect unix shell configuration modification. Adversaries may establish persistence through executing malicious commands
Matching passage: Sigma rule: Detect unix shell configuration modification. Adversaries may establish persistence through executing malicious commands. Logsource: linux / auditd. Rule: title: Unix Shell Configuration Modification id: a94cdd87-6c54-4678-a6cc-2814ffe5a13d related: - id: e74e15cc-c4b6-4c80-b7eb-dfe49feb7fe9 type: obsolete status: test description: Detect unix shell configuration modification. Adversaries may establish persistence through executing malicious commands triggered when a new shell is opened. references: - https://objective-see.org/blog/blog_0x68.html - https://web.archive.org/web/20221204161143/https://www.glitch-cat.com/p/green-lambert-and-attack - https://www.anomali.com/blog/pulling-linux-rabbit-rabbot-malware-out-of-a-hat author: Peter Matkovski, IAI date: 2023-03-06 modified: 2023-03-15 tags: - attack.privilege-escalation - attack.persistence - attack.t1546.004 logsource: product: linux service: auditd detection: selection: type: PATH name: - /etc/shells - /etc/profile - /etc/profile.d/* - /etc/bash.bashrc - /etc/bashrc - /etc/zsh/zprofile - /etc/zsh/zshrc - /etc/zsh/zlogin - /etc/zsh/zlogout - /etc/csh.cshrc - /etc/csh.login - /root/.bashrc - /root/.bash_profile - /root/.profile - /root/.zshrc - /root/.zprofile - /home/*/.bashrc - /home/*/.zshrc - /home/*/.bash_profile - /home/*/.zprofile - /home/*/.profile - /home/*/.bash_login - /home/*/.bash_logout - /home/*/.zlogin - /home/*/.zlogout condition: selection falsepositives: - Admin or User activity are expected to generate some false positives level: medium
Near-miss passage: Sigma rule: Detects a highly relevant Antivirus alert that reports a web shell. It's highly recommended to tune this rule to the spe. Logsource: antivirus. Rule: title: Antivirus - Web Shell Detection Signature id: fdf135a2-9241-4f96-a114-bb404948f736 status: test description: 'Detects a highly relevant Antivirus alert that reports a web shell. It''s highly recommended to tune this rule to the specific strings used by your anti virus solution by downloading a big WebShell repository from e.g. github and checking the matches. This event must not be ignored just because the AV has blocked the malware but investigate, how it came there in the first place. ' references: - https://www.nextron-systems.com/?s=antivirus - https://github.com/tennc/webshell - https://www.virustotal.com/gui/file/bd1d52289203866645e556e2766a21d2275877fbafa056a76fe0cf884b7f8819/detection - https://www.virustotal.com/gui/file/308487ed28a3d9abc1fec7ebc812d4b5c07ab025037535421f64c60d3887a3e8/detection - https://www.virustotal.com/gui/file/7d3cb8a8ff28f82b07f382789247329ad2d7782a72dde9867941f13266310c80/detection - https://www.virustotal.com/gui/file/e841675a4b82250c75273ebf0861245f80c6a1c3d5803c2d995d9d3b18d5c4b5/detection - https://www.virustotal.com/gui/file/a80042c61a0372eaa0c2c1e831adf0d13ef09feaf71d1d20b216156269045801/detection - https://www.virustotal.com/gui/file/b219f7d3c26f8bad7e175934cd5eda4ddb5e3983503e94ff07d39c0666821b7e/detection - https://www.virustotal.com/gui/file/b8702acf32fd651af9f809ed42d15135f842788cd98d81a8e1b154ee2a2b76a2/detection - https://www.virustotal.com/gui/file/13ae8bfbc02254b389ab052aba5e1ba169b16a399d9bc4cb7414c4a73cd7dc78/detection author: Florian Roth (Nextron Systems), Arnim Rupp date: 2018-09-09 modified: 2026-06-29 tags: - attack.persistence - attack.t1505.003 logsource: category: antivirus detection: selection: - Signature|startswith: - ASP. - IIS/BackDoor - JAVA/Backdoor - JSP. - Perl. - PHP. - Troj/ASP - Troj/JSP - Troj/PHP - VBS/Uxor - Signature|contains: - ASP_ - 'ASP:' - ASP.Agent - ASP/ - Aspdoor - ASPXSpy - Backdoor.ASP - Backdoor.Java - Backdoor.JSP - Backdoor.PHP - Backdoor.VBS - Backdoor/ASP - Backdoor/Java - Backdoor/JSP - Backdoor/PHP - Backdoor/VBS - C99shell - Chopper - filebrowser - JSP_ - 'JSP:' - JSP.Agent - JSP/ - 'Perl:' - Perl/ - PHP_ - 'PHP:' - PHP.Agent - PHP/ - PHPShell - PShlSpy - SinoChoper - Trojan.ASP - Trojan.JSP - Trojan.PHP - Trojan.VBS - VBS.Agent - VBS/Agent - Webshell condition: selection falsepositives: - Unlikely level: high