Using a methodology first seen in 2020, an unknown threat actor has been exploiting a three-year-old bug in the Telerik UI web application framework to take control of web servers, installing Cobalt Strike beacons and other malware in the process.

In the weeks following the initial, 2019 disclosure of the vulnerability, attackers scanned the internet for vulnerable applications.…

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Summary

Update June 2, 2022:

This Cybersecurity Advisory (CSA) has been updated with additional indicators of compromise (IOCs) and detection signatures, as well as tactics, techniques, and procedures (TTPs) from trusted third parties. 

Update End

The Cybersecurity and Infrastructure Security Agency (CISA) is releasing this CSA to warn organizations that malicious cyber actors, likely advanced persistent threat (APT) actors, are exploiting CVE-2022-22954 and CVE-2022-22960 separately and in combination.…

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Background

Since the Log4J vulnerability was exposed, we see more and more malware jumped on the wagon, Elknot, Gafgyt, Mirai are all too familiar, on February 9, 2022, 360Netlab’s honeypot system captured an unknown ELF file propagating through the Log4J vulnerability. What stands out is that the network traffic generated by this sample triggered a DNS Tunnel alert in our system, We decided to take a close look, and indeed, it is a new botnet family, which we named B1txor20 based on its propagation using the file name “b1t”, the XOR encryption algorithm, and the RC4 algorithm key length of 20 bytes.…

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