Google’s threat hunting unit has again intercepted an active North Korean APT actor sliding into the DMs of security researchers and using zero-days and rigged software tools to take control of their computers.
Google’s Threat Analysis Group (TAG) on Thursday outed the government-backed hacking team’s social media accounts and warned that at least one actively exploited zero-day is being used and is currently unpatched.
Using platforms like X (the successor to Twitter) as their initial point of contact, the North Korean threat actor cunningly forged relationships with targeted researchers through prolonged interactions and discussions.
“In one case, they carried on a months-long conversation, attempting to collaborate with a security researcher on topics of mutual interest. After initial contact via X, they moved to an encrypted messaging app such as Signal, WhatsApp or Wire. Once a relationship was developed with a targeted researcher, the threat actors sent a malicious file that contained at least one 0-day in a popular software package,” Google explained.
Google did not identify the vulnerable software package.
Google said the zero-day exploit was used to plant shellcode that conducts a series of anti-virtual machine checks and then sends the collected information, along with a screenshot, back to an attacker-controlled command and control domain.
“The shellcode used in this exploit is constructed in a similar manner to shellcode observed in previous North Korean exploits,” Google said, noting that the security defect has been reported to the affected vendor and is in the process of being patched.
Google said it is withholding technical details and analysis of the exploits until a patch is available.
In addition to targeting researchers with zero-day exploits, Google’s malware hunters also caught the APT group distributing a standalone Windows tool that has the stated goal of ‘download debugging symbols from Microsoft, Google, Mozilla and Citrix symbol servers for reverse engineers.’
The source code for the utility, was first published on GitHub a year ago, has been updated multiple times with features to help with the quick and easy downloading symbol information from a number of different sources.
However, Google warns that the tool has been rigged to hijack data from user machines.
“The tool also has the ability to download and execute arbitrary code from an attacker-controlled domain. If you have downloaded or run this tool, TAG recommends taking precautions to ensure your system is in a known clean state, likely requiring a reinstall of the operating system,” Google said.
This isn’t the first documented case of North Korean government hackers targeting security researchers, particularly those that operate in the offensive space.
In January 2021, Google caught a “government-backed entity based in North Korea” targeting and hacking into computer systems belonging to security researchers working on vulnerability research and development at different companies and organizations.
That campaign, which was well organized across multiple online platforms, included drive-by browser compromises from booby-trapped websites and sustained direct-touch activities on social media websites.