At the very least six organizations in South Korea have been focused by the prolific North Korea-linked Lazarus Group as a part of a marketing campaign dubbed Operation SyncHole.
The exercise focused South Korea’s software program, IT, monetary, semiconductor manufacturing, and telecommunications industries, in response to a report from Kaspersky revealed right this moment. The earliest proof of compromise was first detected in November 2024.
The marketing campaign concerned a “subtle mixture of a watering gap technique and vulnerability exploitation inside South Korean software program,” safety researchers Sojun Ryu and Vasily Berdnikov mentioned. “A one-day vulnerability in Innorix Agent was additionally used for lateral motion.”
The assaults have been noticed paving the best way for variants of identified Lazarus instruments similar to ThreatNeedle, AGAMEMNON, wAgent, SIGNBT, and COPPERHEDGE.
What makes these intrusions notably efficient is the doubtless exploitation of a safety vulnerability in Cross EX, a authentic software program prevalent in South Korea to allow using safety software program in on-line banking and authorities web sites to assist anti-keylogging and certificate-based digital signatures.
“The Lazarus group exhibits a powerful grasp of those specifics and is utilizing a South Korea-targeted technique that mixes vulnerabilities in such software program with watering gap assaults,” the Russian cybersecurity vendor mentioned.
The exploitation of a safety flaw in Innorix Agent for lateral motion is notable for the truth that an analogous method has additionally been adopted by the Andariel sub-cluster of the Lazarus Group prior to now to ship malware similar to Volgmer and Andardoor.
The start line of the most recent wave of assaults is a watering gap assault, which activated the deployment of ThreatNeedle after targets visited varied South Korean on-line media websites. Guests who land on the websites are filtered utilizing a server-side script previous to redirecting them to an adversary-controlled area to serve the malware.
“We assess with medium confidence that the redirected web site might have executed a malicious script, concentrating on a possible flaw in Cross EX put in on the goal PC, and launching malware,” the researchers mentioned. “The script then in the end executed the authentic SyncHost.exe and injected a shellcode that loaded a variant of ThreatNeedle into that course of.”
The an infection sequence has been noticed adopting two phases, utilizing ThreatNeedle and wAgent within the early phases after which SIGNBT and COPPERHEDGE for establishing persistence, conducting reconnaissance, and delivering credential dumping instruments on the compromised hosts.
Additionally deployed are malware households similar to LPEClient for sufferer profiling and payload supply, and a downloader dubbed Agamemnon for downloading and executing extra payloads obtained from the command-and-control (C2) server, whereas concurrently incorporating the Hell’s Gate method to bypass safety options throughout execution.
One payload downloaded by Agamemnon is a software designed to hold out lateral motion by exploiting a safety flaw within the Innorix Agent file switch software. Kaspersky mentioned its investigation unearthed a further arbitrary file obtain zero-day vulnerability in Innorix Agent that has since been patched by the builders.
“The Lazarus group’s specialised assaults concentrating on provide chains in South Korea are anticipated to proceed sooner or later,” Kaspersky mentioned.
“The attackers are additionally making efforts to reduce detection by creating new malware or enhancing present malware. Specifically, they introduce enhancements to the communication with the C2, command construction, and the best way they ship and obtain information.”