Threat Detection Update 18-June-2024 | Stamus Networks (2024)

The Week in Review from Stamus Labs

Welcome to the weekly threat detection update report from Stamus Networks. Each week, you will receive this email with a summary of the updates.

Current Stamus Threat Intelligence (STI) release version: 1075

This week, in addition to daily ruleset and IOC updates, we provided Stamus Security Platform customers with the following improved defense(s):

• New threat detection(s) added [1]: 6 (Potentially Unwanted Program, PocoProxy, CCoreDoor, PhantomNet, Merlin Command and Control framework, Silverfox)
• Major changes to detections(s) [2]: 198
• Updated threat detection(s) [3]: 241

Note: a "method" as referenced below, is a discrete detection vector for a given threat.

The following detections were added to your Stamus Security Platform (SSP) this past week:

PocoProxy (Generic CnC)

Sophos identified the use of previously unreported malware we call CCoreDoor (concurrently discovered by BitDefender) and PocoProxy, as well as an updated variant of EAGERBEE malware with new capabilities to blackhole communications to anti-virus (AV) vendor domains in the targeted organization’s network. Other observed malware variants include NUPAKAGE, Merlin C2 Agent, Cobalt Strike, PhantomNet backdoor, RUDEBIRD malware, and the PowHeartBeat backdoor. Sophos

PocoProxy - Sophos |

• Total number of detection methods: 3
• Kill chain phase(s): command and control

CCoreDoor (Backdoor)

Sophos identified the use of previously unreported malware we call CCoreDoor (concurrently discovered by BitDefender) and PocoProxy, as well as an updated variant of EAGERBEE malware with new capabilities to blackhole communications to anti-virus (AV) vendor domains in the targeted organization’s network. Other observed malware variants include NUPAKAGE, Merlin C2 Agent, Cobalt Strike, PhantomNet backdoor, RUDEBIRD malware, and the PowHeartBeat backdoor. Sophos

CCoreDoor - Sophos |

• Total number of detection methods: 3
• Kill chain phase(s): command and control

PhantomNet (Backdoor)

Sophos identified the use of previously unreported malware we call CCoreDoor (concurrently discovered by BitDefender) and PocoProxy, as well as an updated variant of EAGERBEE malware with new capabilities to blackhole communications to anti-virus (AV) vendor domains in the targeted organization’s network. Other observed malware variants include NUPAKAGE, Merlin C2 Agent, Cobalt Strike, PhantomNet backdoor, RUDEBIRD malware, and the PowHeartBeat backdoor. Sophos

PhantomNet - Sophos |

• Total number of detection methods: 28
• Kill chain phase(s): command and control
• MITRE ATT&CK: T1587

Merlin Command and Control framework (Generic CnC)

Merlin is a post-exploit Command & Control (C2) tool, also known as a Remote Access Tool (RAT), that communicates using the HTTP/1.1, HTTP/2, and HTTP/3 protocols. HTTP/3 is the combination of HTTP/2 over the Quick UDP Internet Connections (QUIC) protocol. Merlin Command and Control framework

Merlin - Malpedia |

• Total number of detection methods: 6
• Kill chain phase(s): command and control

Silverfox (Trojan)

During the installation process, msi executes a malicious script and releases the payload ee.exe in the C drive. ee.exe decrypts and executes shellcode. Shellcode performs anti-debugging operations through various means, adds the exclusion path of Windows Defender, decrypts the string to obtain the URL, establishes a connection to download the file and decrypts it, obtains multiple URLs, continues to download files and releases them to the specified path. The files include white files with data signatures, malicious dlls, ffff.pol, ffff, and lop. Shellcode loads the white file, and during the operation of the white file, the malicious dll is loaded. The malicious dll loads ffff.pol into the memory. ffff.pol is a pe file that lacks an MZ header. After adding, it jumps to the entry point for execution. ffff.pol decrypts the ffff.lop file to obtain the dll file and IP address, etc., and executes the export function Edge of the ffff.lop file to establish communication with c2 to obtain instructions to perform operations such as stealing secrets, escalating privileges, and setting automatic startup. Kanuxe

• Total number of detection methods: 4
• Kill chain phase(s): command and control, delivery

The following detections were updated this past week with changes to kill chain phase(s) or MITRE ATT&CK tactic(s)/technique(s):

APT35 (APT)

Magic Hound is an Iranian-sponsored threat group that conducts long term, resource-intensive cyber espionage operations, likely on behalf of the Islamic Revolutionary Guard Corps. They have targeted U.S. and Middle Eastern government and military personnel, academics, journalists, and organizations such as the World Health Organization (WHO), via complex social engineering campaigns since at least 2014. MITRE

• Added kill chain phase(s): delivery
• Previously supported kill chain phase(s): command and control, delivery
• Method added: 9

ClearFake (Exploit Kit)

There are several malicious fake updates campaigns being run across thousands of compromised websites. This campaign appears to have started around July 19th, 2023. Based on a search on PublicWWW of the injection base64 there are at least 434 infected sites. The name is a reference to the majority of the Javascript being used without obfuscation. One noticeable difference from SocGholish is that there appears to be no tracking of visits by IP or cookies. As an analyst you can you go back to the compromised site over and over coming from the same IP and not clearing your browser cache. This also means the site owner is more likely to see the infection as well. When a user visits a compromised website with ClearFake, the page initially loads as normal before the whole page is taken over by a call to action to update Chrome.

On the index page of the compromised site there is a Javascript injection. The Javascript is base64 encoded. Presumably this is a dynamic injection and will change over time to reflect the new host for the initial payload. On the index page of the compromised site there is a Javascript injection. The Javascript is base64 encoded. Presumably this is a dynamic injection and will change over time to reflect the new host for the initial payload. The second web call returns a Javascript that creates an iframe to house the fake update UI. The iframe src is set to a Keitaro endpoint. The response from the Keitaro endpoint is the foundation for the HTML to be rendered within the iframe.

ClearFake Malware Analysis

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, exploitation
• Methods added: 9

Fake Browser (Trojan)

Attackers are utilizing hacked web sites that promote fake browser updates to infect targets with banking trojans. In some cases, post exploitation toolkits are later executed to encrypt the compromised network with ransomware.

Between May and September 2019, FireEye has conducted multiple incident response cases where enterprise customers were infected with malware through fake browser updates.

Hacked sites would display these "fakeupdates" through JavaScript alerts that state the user is using an old version of a web browser and that they should download an offered "update" to keep the browser running "smoothly and securely".

bleepingcomputer

• Added kill chain phase(s): exploitation, delivery
• Previously supported kill chain phase(s): delivery, exploitation
• Methods added: 13

Gh0st (RAT)

gh0st RAT is a remote access tool (RAT). The source code is public and it has been used by multiple groups.

Source: MITRE

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, actions on objectives, delivery
• Methods added: 1

Glupteba (Downloader)

Glupteba is a trojan-type program, malicious software that installs other programs of this type. Cyber criminals distribute Glupteba through malicious advertisem*nts that can be injected into legitimate websites or advertising networks. Research shows that Glubteba can be used to distribute a browser stealer or router exploiter. In any case, this malware should be uninstalled immediately. Pcrisk

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control
• Methods added: 1

Lumma (Data Theft)

Lumma is an information stealer written in C, sold as a Malware-as-a-Service by LummaC on Russian-speaking underground forums and Telegram since at least August 2022. Lumma's capabilities are those of a classic stealer, with a focus on cryptocurrency wallets, and file grabber capabilities. Malpedia

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): actions on objectives, command and control, installation
• Methods added: 93

Parrot TDS (Trojan)

Parrot TDS acts as a gateway for further malicious campaigns to reach potential victims. In this particular case, the infected sites’ appearances are altered by a campaign called FakeUpdate (also known as SocGholish), which uses JavaScript to display fake notices for users to update their browser, offering an update file for download. The file observed being delivered to victims is a remote access tool. Avast

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, delivery
• Methods added: 3

RAT Generic (RAT)

Remote Access Trojans are programs that provide the capability to allow covert surveillance or the ability to gain unauthorized access to a victim PC. Remote Access Trojans often mimic similar behaviors of keylogger applications by allowing the automated collection of keystrokes, usernames, passwords, screenshots, browser history, emails, chat lots, etc. Remote Access Trojans differ from keyloggers in that they provide the capability for an attacker to gain unauthorized remote access to the victim machine via specially configured communication protocols which are set up upon initial infection of the victim computer. This backdoor into the victim machine can allow an attacker unfettered access, including the ability to monitor user behavior, change computer settings, browse and copy files, utilize the bandwidth (Internet connection) for possible criminal activity, access connected systems, and more. Malwarebytes

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): installation, command and control, actions on objectives
• Methods added: 3

SocGholish (Social Engineering)

It leverages compromised websites and performs some of the most creative fingerprinting checks we’ve seen, before delivering its payload (NetSupport RAT). Malwarebytes

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, exploitation, delivery, reconnaissance, actions on objectives
• Methods added: 7

TA4903 (APT)

An advanced persistent threat (APT) is a stealthy computer network threat actor, typically a nation state or state-sponsored group, which gains unauthorized access to a computer network and remains undetected for an extended period. In recent times, the term may also refer to non-state sponsored groups conducting large-scale targeted intrusions for specific goals.

Such threat actors' motivations are typically political or economic. To date, every major business sector has recorded instances of attacks by advanced actors with specific goals seeking to steal, spy or disrupt. These include government, defense, financial services, legal services, industrial, telecoms, consumer goods, and many more. Some groups utilize traditional espionage vectors, including social engineering, human intelligence and infiltration to gain access to a physical location to enable network attacks. The purpose of these attacks is to place custom malicious code on one or multiple computers for specific tasks.

Source: Wikipedia

• Added kill chain phase(s): delivery
• Previously supported kill chain phase(s): delivery
• Methods added: 30

TA582 (APT)

An advanced persistent threat (APT) is a stealthy computer network threat actor, typically a nation state or state-sponsored group, which gains unauthorized access to a computer network and remains undetected for an extended period. In recent times, the term may also refer to non-state sponsored groups conducting large-scale targeted intrusions for specific goals.

Such threat actors' motivations are typically political or economic. To date, every major business sector has recorded instances of attacks by advanced actors with specific goals seeking to steal, spy or disrupt. These include government, defense, financial services, legal services, industrial, telecoms, consumer goods, and many more. Some groups utilize traditional espionage vectors, including social engineering, human intelligence and infiltration to gain access to a physical location to enable network attacks. The purpose of these attacks is to place custom malicious code on one or multiple computers for specific tasks.

Source: Wikipedia

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control
• Methods added: 3

Trojan Downloader (Downloader)

A Trojan downloader is a type of Trojan horse that downloads and installs files, often malicious programs. A Trojan horse is a type of software that looks legitimate but can be malicious in nature. Sometimes these programs can be downloaded onto a device without the user’s knowledge or consent. A Trojan’s purpose is to damage, disrupt, steal, or generally inflict some other harm on your computer and devices. Norton

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, delivery, actions on objectives, installation
• Methods added: 1

Unknown APT (APT)

An adversary with sophisticated levels of expertise and significant resources, allowing it through the use of multiple different attack vectors (e.g., cyber, physical, and deception), to generate opportunities to achieve its objectives which are typically to establish and extend its presence within the information technology infrastructure of organizations for purposes of continually exfiltrating information and/or to undermine or impede critical aspects of a mission, program, or organization, or place itself in a position to do so in the future; moreover, the advanced persistent threat pursues its objectives repeatedly over an extended period of time, adapting to a defender’s efforts to resist it, and with determination to maintain the level of interaction needed to execute its objectives. NIST.)

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, delivery
• Methods added: 24

XWorm (RAT)

During a routine threat-hunting exercise, Cyble research labs discovered a dark web post where a malware developer was advertising a powerful Windows RAT. Cyble

• Added kill chain phase(s): command and control
• Previously supported kill chain phase(s): command and control, delivery
• MITRE ATT&CK added: T1573
• Previously existing MITRE ATT&CK: T1573
• Methods added: 1

The following threat detection(s) were improved this past week with new or updated threat methods.

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