Rewterz Threat Alert – Cobalt Strike Emerging Malware Campaign – Active IOCs

Severity

High

Analysis Summary

Cobalt Strike first appeared in 2012 in response to alleged flaws in the Metasploit Framework, an existing red team (penetration testing) tool. Cobalt Strike 3.0 was released in 2015 as a stand-alone opponent emulation platform. However, researchers began observing threat actors using Cobalt Strike by 2016. Cobalt Strike’s use in hostile activities was previously connected with huge cybercriminal operations like TA3546 and APT40. Two-thirds of detected Cobalt hit efforts from 2016 to 2018 were attributable to well-resourced cybercrime organizations or APT groups, according to researchers.

Cobalt Strike lets the attacker install a ‘Beacon’ agent on the target PC which provides the attacker with a plethora of capabilities, including command execution, file transfer, keylogging, mimikatz, port scanning, and privilege escalation. Cobalt Strike includes a toolkit called Artifact Kit that is used to create shellcode loaders. 

Researchers discovered a new wave of phishing attacks in September that infect job seekers in the United States and New Zealand with Cobalt Strike beacons. The malware campaign used the lure of a job in order to infect victims with leaked versions of Cobalt Strike beacons.

Researchers discovered a new wave of phishing attacks in September that infect job seekers in the United States and New Zealand with Cobalt Strike beacons. The malware campaign used the lure of a job in order to infect victims with leaked versions of Cobalt Strike beacons. It was observed that Cobalt Strike is not the only piece of malware used in the attacks. In certain situations, individuals were instead infected with a different type of information-stealing malware known as RedLine or an Amadey botnet executor.

Impact

• Data Exfiltration
• Information Theft

Indicators of Compromise

MD5

06b8feae2c9d9f2940cb9dca40d553c3
b4a4d73df41c87b9cc2405bc8d888fc4
4f86eb0c1fac722e4c7b4f6f089bd127
fbfb03cdcf907071420f85ad13dbd281

SHA-256

93b0f19011468a4864c114bcbcfc55f460e2c789b14ea893c26ce450d3c21a9e
a88adca4ef9d73fe83e6ca9beb9670f5e8cb70bde8cd93c774bbddcabbf266bb
89a1a6cb000a66b841ad26a8d0d5af507cc17efc00a109d61d52a65caa4cef43
0afe4ced95773f65946fd82e310cd190d2b2c6655ed3113f23c40ad3822c2ccd

SHA-1

b246ed8055ad9e7bb760795e054224d406ec8a20
50fc8ae12d10e4b56e6525d08eb7850ebf02b246
9d459b6ebc01d6e937785e1e118000bebdd3f700
bb8023e32cbb7526aa514cc62e1ab8244c10664a

Remediation

• Block all threat indicators at your respective controls.
• Search for Indicator of compromise (IOCs)  in your environment utilizing your respective security controls
• Emails from unknown senders should always be treated with caution.
• Never open links or attachments from unknown senders.
• Ensure that general security policies are employed including: implementing strong passwords, correct configurations, and proper administration security policies.
• Limit access to administrative accounts and portals to only relevant personnel and make sure they are not publicly accessible.
• Patch and upgrade any platforms and software timely and make it into a standard security policy. Prioritize patching known exploited vulnerabilities and zero-days