Article
RansomHub Leverages New “Betruger” Backdoor
Arete Analysis
Combating Ransomware
Security researchers have discovered a custom backdoor called “Betruger” that has been linked to several recent RansomHub ransomware attacks. The Betruger malware is highly sophisticated, offering various built-in capabilities to minimize the number of malicious tools required during ransomware attacks. Unlike typical ransomware that relies on public malware tools like Mimikatz and Cobalt Strike, Betruger is designed to perform multiple functions, streamlining the attack process.
What’s Notable and Unique
Analysis of the Betruger backdoor revealed that it incorporates functionality typically found in several pre-ransomware tools, such as screenshotting, keylogging, uploading files to a command and control (C2) server, network scanning, privilege escalation, and credential dumping.
The functionality of Betruger suggests that it may have been developed to reduce the number of new tools deployed on a targeted network while preparing for a ransomware attack.
Betruger is commonly disguised with filenames such as ‘mailer.exe’ and ‘turbomailer.exe’ to make it appear as legitimate software. However, the backdoor has no actual mailing functionality, and it is likely that threat actors chose these names to mimic a legitimate application and avoid detection.
Betruger is one of several tools used by RansomHub affiliates in recent months as they leverage techniques like Bring Your Own Vulnerable Driver (BYVOD) to disable security solutions. Additionally, RansomHub exploits vulnerabilities such as CVE-2022-24521 (Windows Privilege Escalation) and CVE-2023-27532 (Veeam Backup credential leak). Other tools commonly used include Impacket, Rclone, Mimikatz, ScreenConnect, and SystemBC to facilitate credential dumping, remote access, and data exfiltration.
Analyst Comments
RansomHub was one of the top RaaS groups to emerge in the second half of 2024, as reported in Arete’s recently published 2024 Annual Crimeware Report. RansomHub rapidly expanded its operations and displayed a willingness to work with individual affiliates as well as existing threat groups. The development of highly sophisticated malware like Betruger demonstrates the group’s ability to continuously improve its capabilities and further positions RansomHub as a major player in 2025’s ransomware threat landscape.ransomware threat landscape.
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Article
CMS Vulnerability Leads to ClickFix Campaign
Threat actors compromised at least 700 education and technology websites in a recent ClickFix campaign by exploiting a critical SQL injection flaw (CVE-2026-26980) in the Ghost content management system (CMS). Adversaries combined the vulnerability with the ClickFix social engineering tactic to steal admin keys and inject a malicious JavaScript that delivers a fake Cloudflare or CAPTCHA verification pop-up, tricking victims into copying and pasting a malicious command into their systems.
What’s Notable and Unique
Rather than targeting the end user first, this campaign is unique in its initial exploitation of the system, followed by social engineering attempts. This hybrid attack style is likely being leveraged to bypass traditional defenses.
This recent campaign also highlights how trusted web properties can be weaponized at scale and coupled with unpatched CMS vulnerabilities. Rather than using the CMS compromise to perpetrate a single attack, threat actors turned it into a supply-chain attack that ultimately affected over 700 trusted websites.
Analyst Comments
As network defenders and their tools enhance threat detection capabilities, adversaries increasingly seek methods to bypass these defenses. By combining vulnerability exploitation, social engineering techniques, and staging for ancillary attacks, this campaign successfully bypassed traditional defenses and inflicted significant impact. Defending against hybrid cyberattacks requires comprehensive security controls beyond simply patching vulnerabilities. Organizations should focus on limiting movement within the environment, detecting abuse of trusted applications, and preventing end-user manipulation.
Sources
700+ education and tech websites hijacked in huge ClickFix malware campaign
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Article
Threat Actors Leverage Fake JPEG Files for Initial Access
In a recent campaign, researchers observed threat actors using fake JPEG image files as a delivery mechanism to initiate the deployment of additional malicious components. The false JPEG files are typically distributed via phishing emails or other social engineering-based lures, and are actually PowerShell-based malware that deploys a trojanized version of ConnectWise ScreenConnect to establish and maintain persistence in the compromised environment.
What’s Notable and Unique
This campaign leverages JPEG images as the initial lure, where the images are not merely decoys but part of the infection workflow. Victims are typically led to download or open an image that triggers hidden execution logic or redirects them to a payload-delivery sequence that initiates later stages of the intrusion chain.
The attack chain is designed to blend into legitimate environments, making detection more difficult. Execution typically relies on scripted or native Windows components, often including PowerShell or other living-off-the-land binaries, enabling fileless or near-fileless execution and reducing forensic artifacts on disk.
The multistage design ensures that the initial JPEG does not directly contain the full payload but instead triggers retrieval or decryption steps that progressively assemble the final malicious components in memory.
Analyst Comments
This campaign illustrates how threat actors continue to blur the line between legitimate file handling and malicious execution chains, indicating potential overlap with remote management or administrative tooling. The use of JPEG-based staging combined with script-based execution reflects a broader evolution toward a stealth-first intrusion design, in which file formats serve as triggers rather than payload containers.
Sources
OPERATION SILENTCANVAS : JPEG BASED MULTISTAGE POWERSHELL INTRUSION
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