Description of Campaign
The RedLine information stealer is being delivered and used by the Rig Exploit Kit to gather targeted information from compromised machines. The attack takes advantage of an Internet Explorer vulnerability, CVE-2021-26411, to deliver the information stealer and collect usernames, system hardware, installed browsers as well as installed anti-virus software, passwords, crypto wallets, chat logs, and VPN credentials. Once complete, the gathered information is then exfiltrated to the attacker's C2.

Our ATR Team gathers and analyzes information from multiple open and closed sources before disseminating intelligence reports. This campaign was researched by Bitdefender and shared publicly.

How to use this article:

1. If a Threat Hunting table has been created, use the rules contained to search for malware related to this campaign. 
2. Review the product detection table and confirm that your environment is at least on the specified content version.
   To download the latest content versions, go to the Security Updates page.
3. Scroll down and review the "Product Countermeasures" section of this article. Consider implementing them if they are not already in place.
4. Review KB91836 - Countermeasures for entry vector threats.
5. Review KB87843 - Dynamic Application Containment rules and best practices.
6. Review KB82925 - Identify what rule corresponds to an Adaptive Threat Protection and Threat Intelligence Exchange event.

Threat Hunting

YARA

rule MALWARE_Win_RedLineDropperAHK { meta: author = "ditekSHen" description = "Detects AutoIt/AutoHotKey executables dropping RedLine infostealer" clamav_sig = "MALWARE.Win.Trojan.RedLineDropper-AHK" strings: $s1 = ".SetRequestHeader(\"User-Agent\",\" ( \" OSName \" | \" bit \" | \" CPUNAme \"\"" ascii $s2 = ":= \" | Windows Defender\"" ascii $s3 = "WindowSpy.ahk" wide $s4 = ">AUTOHOTKEY SCRIPT<" fullword wide condition: uint16(0) == 0x5a4d and all of them }

This Knowledge Base article discusses a specific threat that's being tracked. The list of IOCs will change over time; check MVISION Insights for the latest IOCs.
 
Campaign IOC

Type	Value
SHA256	B78615662C8C362D920C3F9273352D0DA085610774F1FA5A96CDA4EC50CA0507
IP-DST	188.227.106.3

Minimum Content Versions

Content Type	Version
V2 DAT (VirusScan Enterprise)	10341
V3 DAT (Endpoint Security)	4793

  
Detection Summary                               

IOC	Scanner	Detection
B78615662C8C362D920C3F9273352D0DA085610774F1FA5A96CDA4EC50CA0507	AVEngine V2	PWS-FDHJ!877A637058B7
	AVEngine V3	PWS-FDHJ!877A637058B7
	JTI (ATP Rules)	JTI/Suspect.196612!877a637058b7
	RP Static	-
	RP Dynamic	-

Minimum set of Manual Rules to improve protection to block this campaign:

IMPORTANT: Always follow best practices when you enable new rules and signatures.

When you implement new rules or signatures, always set them to Report mode first and check the alerts generated. Resolve any issues that arise and then set the rules to Block. This step mitigates against triggering false positives and allows you to refine your configuration.

For more information, see KB87843 - List of and best practices for Endpoint Security Dynamic Application Containment rules.

Endpoint Security - Advanced Threat Protection:
Host Intrusion Prevention:
Aggressive set of Manual Rules to improve protection to block this campaign:

IMPORTANT: Always follow best practices when you enable new rules and signatures.

When you implement new rules or signatures, always set them to Report mode first and check the alerts generated. Resolve any issues that arise and then set the rules to Block. This step mitigates against triggering false positives and allows you to refine your configuration.

For more information, see KB87843 - List of and best practices for Endpoint Security Dynamic Application Containment rules.

VirusScan Enterprise - Access Protection Rules:
Host Intrusion Prevention: