October 15, 2024

ESET Analysis

ESET Analysis has carried out a complete technical evaluation of Gamaredon’s toolset used to conduct its cyberespionage actions targeted in Ukraine

Cyberespionage the Gamaredon way: Analysis of toolset used to spy on Ukraine in 2022 and 2023

The conflict in Ukraine, which began in February 2014 and intensified with Russia’s invasion of the nation on February 24th, 2022, exemplifies a multifaceted conflict, rife with disinformation campaigns and cyberwarfare. All through these years, ESET Analysis has revealed a number of high-profile cyberattacks carried out by Russia-aligned superior persistent menace (APT) teams focusing on Ukrainian entities and Ukrainian audio system, analyzed numerous operations, and saved observe of a number of APT teams specializing in this area due to the conflict.

On this analysis, we determined to look at the operations of Gamaredon, the Russia-aligned group that has been lively since a minimum of 2013 and is presently essentially the most engaged APT group in Ukraine. The depth of the bodily battle has noticeably elevated since 2022, however it’s value noting that the extent of exercise from Gamaredon has remained constant – the group has been methodically deploying its malicious instruments towards its targets since nicely earlier than the invasion started.

We now have analyzed hundreds of samples whereas conducting a complete technical evaluation of Gamaredon’s toolset used to conduct its cyberespionage actions in 2022 and 2023; we reveal the outcomes of our evaluation in our white paper, which you’ll learn in full right here:

Within the white paper, we share particulars about Gamaredon’s ever-changing obfuscation methods and quite a few strategies used for bypassing domain-based blocking. These techniques pose a major problem to monitoring efforts, as they make it more durable for techniques to routinely detect and block the group’s instruments. However, throughout our analysis, we managed to establish and perceive these techniques, and preserve observe of Gamaredon’s actions. We additionally describe the instruments which can be most prevalent or fascinating in another method with the intention to shed extra mild on the relationships that exist among the many instruments and to assist create an even bigger image of the instruments’ ecosystem.

Victimology and group background

Gamaredon has been attributed by the Security Service of Ukraine (SSU) to the 18th Heart of Info Safety of the FSB, working out of occupied Crimea. We consider this group to be collaborating with one other menace actor that we found and named InvisiMole.

As evidenced over time by ESET telemetry, in several reports from CERT-UA, and from different official Ukrainian our bodies, the vast majority of Gamaredon’s assaults are directed towards Ukrainian governmental establishments. To our shock, in April 2022 and February 2023, we noticed a couple of makes an attempt to compromise targets in a number of NATO nations, specifically Bulgaria, Latvia, Lithuania, and Poland, however no profitable breaches have been noticed.

Between November 1st, 2022 and December 31st 2023, we noticed greater than a thousand distinctive machines in Ukraine that have been attacked by Gamaredon. The seven-day transferring common of day by day additions is visualized in Determine 1.

Determine 1. Seven-day transferring common of distinctive machines attacked in Ukraine

Noisy and reckless, however nonetheless harmful

To compromise new victims, Gamaredon conducts spearphishing campaigns after which makes use of its customized malware to weaponize Phrase paperwork and USB drives accessible to the preliminary sufferer and which can be anticipated to be shared with additional potential victims.

Based on our long-term observations, Gamaredon, in contrast to most APT teams, doesn’t attempt to be stealthy and stay hidden so long as attainable through the use of novel strategies when conducting cyberespionage operations, however moderately the operators are reckless and don’t thoughts being found by defenders throughout their operations. Though they don’t care a lot about being noisy, they apparently put in a number of effort to keep away from being blocked by safety merchandise and take a look at very arduous to take care of entry to compromised techniques.

Sometimes, Gamaredon makes an attempt to protect its entry by deploying a number of easy downloaders or backdoors concurrently. The shortage of sophistication of Gamaredon instruments is compensated by frequent updates and use of repeatedly altering obfuscation.

A shift in direction of VBScript and PowerShell

Gamaredon’s toolset has undergone a number of modifications over time. In 2022, the group slowly began to shift towards the usage of VBScript and PowerShell in tandem, and Gamaredon nearly fully ditched the usage of SFX archives, which had been its main tactic beforehand. Throughout 2023, Gamaredon notably improved its cyberespionage capabilities and developed a number of new instruments in PowerShell, with the concentrate on stealing useful information, for instance from net functions working inside web browsers, e mail shoppers, and instantaneous messaging functions akin to Sign and Telegram.

Nevertheless, PteroBleed, an infostealer we found in August 2023, additionally focuses on stealing information associated to a Ukrainian navy system and from a webmail service utilized by a Ukrainian governmental establishment. The timeline of latest instruments launched in 2022 and 2023 is proven in Determine 2; apart from PteroScreen, all of them have been found by ESET Analysis.

Determine 2. Timeline of latest instruments added to Gamaredon’s arsenal

Generally, we will categorize Gamaredon’s toolset into downloaders, droppers, weaponizers, stealers, backdoors, and advert hoc instruments. The group makes use of a mix of general-purpose and devoted downloaders to ship payloads. Droppers are used to ship numerous VBScript payloads; weaponizers alter properties of present recordsdata or create new recordsdata on related USB drives, and stealers exfiltrate particular recordsdata from the file system. Moreover, backdoors function distant shells, and advert hoc instruments carry out particular features, like a reverse SOCKS proxy or payload supply utilizing the respectable command line program rclone.

Quick switching of C&C IP addresses and domains

Our evaluation additionally sheds mild on the group’s community infrastructure. Gamaredon makes use of a method often known as fast flux DNS – continuously altering its command and management (C&C) servers’ IP addresses, normally a number of instances per day, to keep away from IP-based blocking. The group additionally continuously registers and updates many new C&C domains to keep away from domain-based blocking, primarily utilizing .ru because the top-level area (TLD).

Gamaredon has additionally demonstrated resourcefulness by using numerous strategies to evade network-based detections, leveraging third-party companies akin to Telegram, Cloudflare, and ngrok.

Regardless of the relative simplicity of its instruments, Gamaredon’s aggressive method and persistence make it a major menace. Given the continuing conflict within the area, we count on Gamaredon to proceed in its concentrate on Ukraine.

For a extra detailed evaluation and technical breakdown of Gamaredon’s instruments and actions, you’ll be able to entry the total ESET Analysis white paper here.

A complete record of indicators of compromise (IoCs) could be present in our GitHub repository and the Gamaredon white paper.