Technical Tip: Using FortiAnalyzer to detect activities related to the Akira Ransomware | CVE-2020-3259, CVE-2023-20269

emorlang_FTNT · ‎04-23-2024

Description

This article describes how to use a custom event handler in FortiAnalyzer to raise alerts for incident response related to attacks that attempt to leverage the Akira Ransomware. A report is also provided to gain historical visibility into the logs.

Note that this article provides alpha files which are automatically generated. The article will be continually updated as more information becomes available.

Scope

This article contains the files necessary to load an event handler and report into the FortiAnalyzer for either a Fabric ADOM or a FortiGate ADOM. The Fabric report and event handler leverage logs from other Fortinet products that can be used to detect the attack in addition to FortiGate logs.

For more information about this attack, see the following FortiGuard Outbreak Alert:

Akira Ransomware

Solution

What is included in Fortinet_Akira Ransomware.zip:

Akira Ransomware_event-handler.json.

This event handler helps identify Akira Ransomware detected by FortiGate and other Fortinet products. This event handler is configured for Fabric ADOMs.
Akira Ransomware_report.dat.

This report displays the findings on Akira Ransomware attacks from FortiGate and other Fortinet products. This report is configured for Fabric ADOMs.
fgt_Akira Ransomware_event-handler.json.

The event handler for FortiGate ADOMs is configured for FortiGate logs only.
fgt_Akira Ransomware_report.dat.

The report for FortiGate ADOMs includes FortiGate charts only.

Steps:

Download the Fortinet_Akira Ransomware.zip file (contains 4 files).
Unzip Fortinet_Akira Ransomware.zip.
Import Akira Ransomware_event-handler.json or fgt_Akira Ransomware_event-handler.json event handler:

Choose an ADOM (if ADOMs are enabled). The ADOM may have the Fabric or FortiGate type.
Choose the FortiSOC module.
Select Event Handler List.
Select the Import option under More.
Select the appropriate event handler depending on the ADOM type.

event handler.png

Result:

The event handler is enabled and will be triggered if the appropriate logs are received following the import of the event handler.

Edit the event handler to customize the notification section.

Import Akira Ransomware_report.dat or fgt_Akira Ransomware_report.dat to Reports:

Choose an ADOM (if ADOMs are enabled). The ADOM may have the Fabric or FortiGate type.
Choose the Report module.
Select the Import option under 'More'.
Select the appropriate file for the ADOM type to add the report to the ADOM.

Result:

The Akira Ransomware_report can be run anytime as determined by an admin user.