An investigation has found that a North Korea-linked threat actor, known as Kimsuky, has been involved in the use of a malicious Google Chrome extension to steal sensitive information to collect information as part of an ongoing intelligence collection effort. Observing the activity in early March 2024, Zscaler ThreatLabz has codenamed the extension TRANSLATEXT, emphasizing its ability to gather email addresses, usernames, passwords, cookies, and screenshots as well as its ability to gather this information.
This targeted campaign is said to have targeted South Korean academia, specifically those focused on North Korean politics. There is a notorious North Korean hacker group known as Kimsuky that has been active since 2012, perpetrating cyber espionage and financial-motivated attacks against South Korean businesses. Kimsuky is widely known as a notorious hacker crew. In the remote server's PowerShell script, general information about the victim is uploaded as well as creating a Windows shortcut that enables a user to retrieve another script from the remote server through a PowerShell script. TRANSLATEXT's exact delivery method remains unclear, which makes it even more difficult for defenders to protect themselves from it.
Despite this, Kimsuky is well known for utilizing sophisticated spear-phishing and social engineering attacks to trick the target into initiating the infection process. Two files appear to be connected to Korean military history when the attack begins, a ZIP archive that appears to contain two files, a Hangul Word Processor document and an executable file. Once the executable file has been launched, it retrieves a PowerShell script from the attacker's server. In addition to exporting the victim's information to a GitHub repository, this script also downloads additional PowerShell code via a Windows shortcut (LNK) file and executes it.
It is clear from this multi-stage attack process that Kimsuky is an extremely sophisticated and well-planned operation. By using a familiar and seemingly legitimate document, the attackers decrease the chances of the targets being suspicious. As well as displaying an innovative method of blending malicious activities into regular internet traffic, GitHub is also utilized in the initial data export process, resulting in a much harder time finding and blocking malicious actions for traditional security systems. There are a few groups that are also associated with the Lazarus cluster or part of the Reconnaissance General Bureau (RGB).
For instance, APT43, ARCHIPELAGO, Black Banshee, Emerald Sleet, Springtail, and Velvet Chollima are groups that are affiliated with the Lazarus cluster. There have been several incidents in the last few weeks in which the group has weaponized a vulnerability in Microsoft Office (CVE-2017-11882), distributed a keylogger, and used job-themed lures in attacks aiming at the aerospace and defence industries to drop an espionage tool that gathers data and executes secondary payloads. "The backdoor is unknown to the public and the attacker can conduct basic reconnaissance, drop additional payloads, and then take over or remotely control the computer."
CyberArmor said. Despite Kimsuky's recent involvement in cyber espionage, it has given this campaign the name Niki. It is no secret that Kimsuky is not a new player. Since at least 2012, the group has been active and has developed a reputation for orchestrating cyber-espionage and financial-motivated attacks primarily on South Korean institutions, which has earned them a reputation as a notorious group. It has been reported that the group has stolen classified information, and committed financial fraud, and ransomware attacks. Throughout history, they have been one of the most formidable cyber threat actors associated with North Korea due to their adaptability and persistence.
There is no doubt that Kimsuky is capable of blending cyber espionage with financially motivated operations, indicating a versatile approach to achieving the North Korean regime's objectives, whether they are to gather intelligence or generate revenue to support it. As of right now, it is not clear what is the exact mechanism for accessing the newly discovered activity, although it is known that the group is known for utilizing spear-phishing and social engineering attacks to launch the infection cycle.
It is believed that the attack began with the delivery of a ZIP archive with the intent of containing Korean military history at the time, which contains two files: a word processor document in Hangul and an executable at the time of the attack. As soon as the executable is launched, a PowerShell script is extracted from a server controlled by the attacker that downloads additional PowerShell code with the aid of a Windows shortcut file (LNK) and creates a GitHub repository where the compromised victim's information is periodically uploaded.
After the GitHub repository has been created, the attacker deletes the LNK file in question. This is the statement posted by Zscaler, a security company that found a GitHub account, created on February 13, 2024, that briefly hosted the TRANSLATEXT extension under the name "GoogleTranslate.crx," regardless of how it is distributed at the moment. TRANSLATEXT, which masquerades as Google Translate, incorporates JavaScript code to bypass security measures for services like Google, Kakao, and Naver; siphon email addresses, credentials, and cookies; capture browser screenshots; and exfiltrate stolen data. It's also designed to fetch commands from a Blogger Blogspot URL to take screenshots of newly opened tabs and delete all cookies from the browser, among others.