Analytics Story: CISA AA24-241A
Description
This story covers the tactics of Iran-based cyber actors exploiting U.S. and foreign organizations across multiple sectors, as detailed in CISA Alert AA24-241A. It focuses on their methods of gaining initial access, establishing persistence, and enabling ransomware attacks through vulnerabilities in public-facing networking devices.
Why it matters
As of August 2024, Iran-based cyber actors continue to exploit organizations across several U.S. sectors and other countries. The FBI assesses that a significant percentage of these operations aim to obtain network access for collaboration with ransomware affiliates. The actors typically use Shodan to identify vulnerable devices, then exploit public-facing networking equipment such as Citrix Netscaler, F5 BIG-IP, and various VPNs. They deploy webshells, create local accounts, and manipulate existing ones to maintain access. Post-exploitation, they repurpose credentials, disable security software, and use remote access tools. The group collaborates with ransomware affiliates like NoEscape, Ransomhouse, and ALPHV, actively participating in network lockdowns and extortion strategies. Defenders should prioritize patching public-facing devices, monitoring for unauthorized accounts and suspicious PowerShell activity, implementing strong access controls, and regularly reviewing logs for signs of compromise.
Detections
Data Sources
Name | Platform | Sourcetype | Source |
---|---|---|---|
CrowdStrike ProcessRollup2 | N/A | crowdstrike:events:sensor |
crowdstrike |
Palo Alto Network Threat | Network | pan:threat |
pan:threat |
Powershell Script Block Logging 4104 | Windows | xmlwineventlog |
XmlWinEventLog:Microsoft-Windows-PowerShell/Operational |
Suricata | N/A | suricata |
suricata |
Sysmon EventID 1 | Windows | xmlwineventlog |
XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
Sysmon EventID 11 | Windows | xmlwineventlog |
XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
Sysmon EventID 12 | Windows | xmlwineventlog |
XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
Sysmon EventID 13 | Windows | xmlwineventlog |
XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
Sysmon EventID 22 | Windows | xmlwineventlog |
XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
Windows Event Log Security 4688 | Windows | xmlwineventlog |
XmlWinEventLog:Security |
Windows Event Log Security 4720 | Windows | xmlwineventlog |
XmlWinEventLog:Security |
Windows Event Log Security 4732 | Windows | xmlwineventlog |
XmlWinEventLog:Security |
Windows Event Log TaskScheduler 200 | Windows | wineventlog |
WinEventLog:Microsoft-Windows-TaskScheduler/Operational |
References
- https://www.cisa.gov/news-events/cybersecurity-advisories/aa24-241a
- https://gist.github.com/MHaggis/7e67b659af9148fa593cf2402edebb41
Source: GitHub | Version: 1