T1205: Traffic Signaling

Kimsuky is a Democratic People's Republic of Korea (DPRK)-based cyber espionage group that has been active since at least 2012. The group initially targeted South Korean government agencies, think tanks, and subject-matter experts in various fields. Its operations expanded to include the United Nations and organizations in the government, education, business services, and manufacturing sectors across the United States, Japan, Russia, and Europe. Kimsuky has focused collection on foreign policy and national security issues tied to the Korean Peninsula, nuclear policy, and sanctions. Kimsuky operations have overlapped with those of other North Korean state-sponsored cyber espionage actors as a result of ad hoc collaborations or other limited resource sharing.[1][2][3][4][5][6]

Kimsuky was assessed to be responsible for the 2014 Korea Hydro & Nuclear Power Co. compromise; other notable campaigns include Operation STOLEN PENCIL (2018), Operation Kabar Cobra (2019), and Operation Smoke Screen (2019).[7][8][9] In 2023, Kimsuky was observed using commercial large language models (LLMs) to assist with vulnerability research, scripting, social engineering and reconnaissance.[10]

DPRK threat actor cluster boundaries overlap in open source reporting, with some security researchers consolidating all attributed North Korean state-sponsored cyber activity under Lazarus Group, rather than tracking operationally distinct subgroups.

Mustang Panda is a China-based cyber espionage threat actor that has been conducting operations since at least 2012. Mustang Panda has been known to use tailored phishing lures and decoy documents to deliver malicious payloads. Mustang Panda has targeted government, diplomatic, and non-governmental organizations, including think tanks, religious institutions, and research entities, across the United States, Europe, and Asia, with notable activity in Russia, Mongolia, Myanmar, Pakistan, and Vietnam. [1][2][3][4][5][6][7][8][9][10][11][12][13]

UNC3886 is a China-nexus cyberespionage group that has been active since at least 2022, targeting defense, technology, and telecommunication organizations located in the United States and the Asia-Pacific-Japan (APJ) regions. UNC3886 has displayed a deep understanding of edge devices and virtualization technologies through the exploitation of zero-day vulnerabilities and the use of novel malware families and utilities.[1][2]

TONESHELL is a custom backdoor that has been used since at least Q1 2021.[1] TONESHELL malware has previously been leveraged by Chinese affiliated actors identified as Mustang Panda.[2][3]

BUSHWALK is a web shell written in Perl that was inserted into the legitimate querymanifest.cgi file on compromised Ivanti Connect Secure VPNs during Cutting Edge.[1][2]

J-magic is a custom variant of the cd00r backdoor tailored to target Juniper routers that was first observed during the J-magic Campaign in mid-2023. J-magic monitors TCP traffic for five predefined parameters or "magic packets" to be sent by the attackers before activating on compromised devices.[1]

PUBLOAD is a stager malware that has been observed installing itself in existing directories such as `C:\Users\Public` or creating new directories to stage the malware and its components.[1] PUBLOAD malware collects details of the victim host, establishes persistence, encrypts victim details using RC4 and communicates victim details back to C2. PUBLOAD malware has previously been leveraged by China-affiliated actors identified as Mustang Panda. PUBLOAD is also known as “NoFive” and some public reporting identifies the loader component as CLAIMLOADER.[2]

A Linux rootkit that provides backdoor access and hides from defenders.

TRANSLATEXT is malware that is believed to be used by Kimsuky.[1] TRANSLATEXT masqueraded as a Google Translate extension for Google Chrome, but is actually a collection of four malicious Javascript files that perform defense evasion, information collection and exfiltration.[1]

REPTILE is an open-source Linux rootkit with multiple components that provides backdoor access and functionality.[1]

Chaos is Linux malware that compromises systems by brute force attacks against SSH services. Once installed, it provides a reverse shell to its controllers, triggered by unsolicited packets. [1]

Uroburos is a sophisticated cyber espionage tool written in C that has been used by units within Russia's Federal Security Service (FSB) associated with the Turla toolset to collect intelligence on sensitive targets worldwide. Uroburos has several variants and has undergone nearly constant upgrade since its initial development in 2003 to keep it viable after public disclosures. Uroburos is typically deployed to external-facing nodes on a targeted network and has the ability to leverage additional tools and TTPs to further exploit an internal network. Uroburos has interoperable implants for Windows, Linux, and macOS, employs a high level of stealth in communications and architecture, and can easily incorporate new or replacement components.[1][2]

SYNful Knock is a stealthy modification of the operating system of network devices that can be used to maintain persistence within a victim's network and provide new capabilities to the adversary.[1][2]

Winnti for Linux is a trojan, seen since at least 2015, designed specifically for targeting Linux systems. Reporting indicates the winnti malware family is shared across a number of actors including Winnti Group. The Windows variant is tracked separately under Winnti for Windows.[1]

Kobalos is a multi-platform backdoor that can be used against Linux, FreeBSD, and Solaris. Kobalos has been deployed against high profile targets, including high-performance computers, academic servers, an endpoint security vendor, and a large internet service provider; it has been found in Europe, North America, and Asia. Kobalos was first identified in late 2019.[1][2]

The RedPenguin project was launched by Juniper in July 2024 to investigate reported malware infections of Juniper MX Series routers. RedPenguin activity was separately attributed to UNC3886 and included the deployment of multiple custom versions of the publicly-available TINYSHELL backdoor on Juniper routers.[1][2]

Cutting Edge was a campaign conducted by suspected China-nexus espionage actors, variously identified as UNC5221/UTA0178 and UNC5325, that began as early as December 2023 with the exploitation of zero-day vulnerabilities in Ivanti Connect Secure (previously Pulse Secure) VPN appliances. Cutting Edge targeted the U.S. defense industrial base and multiple sectors globally including telecommunications, financial, aerospace, and technology. Cutting Edge featured the use of defense evasion and living-off-the-land (LoTL) techniques along with the deployment of web shells and other custom malware.[1][2][3][4][5]