Spark RAT Targets Cambodia, Abuses Vulnerable OPSWAT Driver to Disable Security Tools
Acronis details a Spark RAT campaign against Cambodia abusing the vulnerable OPSWAT ardrv.sys driver (CVE-2026-36425) to disable Microsoft Defender and other security tools.
Acronis TRU analyzed a multi-stage Spark RAT campaign targeting Cambodian individuals and organizations with lures spanning government notices, public health materials, and real estate documents. Attack chains use phishing emails with Inno Setup archives, DLL side-loading via a signed Tencent executable, and BYOVD abuse of the vulnerable OPSWAT ardrv.sys driver (CVE-2026-36425) to terminate security software. Shellcode hidden in PNG files patches AMSI and ETW, establishes scheduled task and service persistence, and injects into vssvc.exe and ctfmon.exe to run the open-source Go-based Spark RAT. Tactics resemble the Silver Fox actor, but Acronis tracks the cluster as unattributed with low confidence.
Orthanc DICOM Server
CISA advisory flags CVE-2026-87020, an integer overflow in Orthanc DICOM Server <1.13.0 causing heap out-of-bounds write and denial of service when decoding crafted PNG/JPEG images.
CISA published ICSMA-26-253-02 for Orthanc DICOM Server versions below 1.13.0, used in healthcare environments worldwide. CVE-2026-87020 (CWE-190) is an integer overflow in pitch and buffer-size computation causing a heap out-of-bounds write when decoding attacker-supplied PNG or JPEG images. An authenticated remote attacker can crash the Orthanc process and cause denial of service; CVSS v3.1 is 8.1 HIGH. CISA states no known public exploitation targeting this flaw has been reported.
Attack hides malware in PNGs and drops custom reverse tunnel on victims' machines
A ClickFix social engineering wave delivers a multi-stage attack that hides malware in PNG files and installs a custom reverse tunnel.
The Register reports a new wave of ClickFix social engineering attacks that trigger a multi-stage infection chain on victim machines. The attack reportedly conceals malware inside PNG image files and deploys a custom reverse tunnel tool for attacker access. Further technical details are limited in the available text.
The Fractured Block Campaign: CARROTBAT Used to Deliver Malware Targeting Southeast Asia
Unit 42 uncovers the Fractured Block campaign using the CARROTBAT dropper to deliver SYSCON and OceanSalt malware in cryptocurrency-themed attacks across Southeast Asia.
Unit 42 identified 29 CARROTBAT dropper samples used in the Fractured Block campaign, delivering decoy documents on cryptocurrencies, exchanges, and Korean political topics. Early samples delivered the SYSCON RAT, which uses FTP for command and control, while later ones dropped the previously reported OceanSalt malware. CARROTBAT supports 11 decoy file formats and uses certutil to download and execute payloads. Initial discovery stemmed from a December 2017 spear phishing attack on a British government agency, with infrastructure overlap tying the campaign to KONNI activity.
ClearFake WebDAV infection chain delivers Amatera stealer, ZigCryptoStealer, and NetSupport Manager
Cisco Talos details ClearFake WebDAV chains delivering Amatera stealer to a Ukrainian government organization, with cryptocurrency and credential theft payloads.
Cisco Talos investigated DLL executions named 'verification.google' via WebDAV UNC paths at a Ukrainian government organization, tracking the actor as UAT-10820 and assessing with moderate confidence the activity is Russian and opportunistic rather than targeted. The infection chain uses ClearFake JavaScript injected via a Cloudflare Worker, EtherHiding storage on BNB Smart Chain contracts, and a ClickFix fake Google CAPTCHA prompt to deliver Amatera stealer. Secondary payloads differ by C2: one loader deploys ZigCryptoStealer with a Go reverse TCP proxy and a vulnerable driver that kills EDR, while the other installs an unauthorized NetSupport Manager with a Russia-based C2. Similar Amatera chains were separately documented by Malwarebytes and Blackpoint Cyber, but with no shared infrastructure.
BraZetsu Malware Turns Compromised Windows Hosts Into Criminal Marketplace Inventory
Group-IB details BraZetsu, a modular Python Windows malware that monetizes compromised-host access through the Infected Marketplace for initial access brokers.
Group-IB attributes BraZetsu to the Exilware threat actor, believed to be native Portuguese speakers targeting Iberian and Latin American e-commerce, financial, industrial, and law enforcement victims. The framework, first observed in early May 2026, uses generative AI for data triage and target prioritization, steals browser histories and digital certificates, and hunts Brazilian CNAB financial remittance files. Access to compromised hosts is sold on the Infected Marketplace from roughly $5.80, letting buyers remotely deploy secondary payloads over WebSocket-linked infrastructure. Some samples evaded detection on VirusTotal; delivery likely uses VBS loaders from a domain also used to distribute the Ousaban banking trojan.
TerminalFix Uses Fake Cloudflare CAPTCHAs to Deploy Reverse
Microsoft details TerminalFix, a ClickFix variant using fake Cloudflare CAPTCHAs to make users run PowerShell payloads with reverse-tunnel implants.
Microsoft disclosed TerminalFix campaigns that direct users to run commands in Windows Terminal or PowerShell instead of the Run dialog, increasing the chance multi-line scripts execute. Compromised websites serve fake Cloudflare CAPTCHA verifications; the resulting PowerShell command downloads a ZIP with legitimate LockScreenContentServer.exe and rogue dui70.dll for DLL sideloading, retrieves payloads hidden in PNG images from attacker domains, persists via Registry Run keys and scheduled tasks, and performs domain trust and Active Directory reconnaissance. A Python-based reverse-tunnel implant (client.py) tunnels arbitrary TCP traffic over an encrypted WebSocket to gitnow[.]dev:443, giving attackers network-level proxy access that could enable privilege escalation, security-tool tampering, data theft or ransomware. Microsoft recommends AppLocker restrictions, PowerShell script block logging and ClickFix awareness training.
AmnesiaStealer Hijacks Chromium Sessions to Give Attackers Live Browser Control on macOS
Jamf details AmnesiaStealer, a new Rust-based macOS infostealer that hijacks Chromium sessions for live attacker-controlled browser access and steals Keychain data.
Jamf Threat Labs disclosed a three-stage macOS infostealer called AmnesiaStealer distributed via a fake GitHub download page using a ClickFix-style lure that tricks users into pasting a Base64 command into Terminal. The Rust payload harvests the Keychain, Apple Notes, Telegram sessions, Safari cookies, and 16 Chromium-family browsers, and captures the system password via a native prompt validated with dscl. A remotely fetched stream_module gives operators hidden, interactive browser control via the Chrome DevTools Protocol, streaming a live session at roughly 3fps. It persists via a root LaunchDaemon impersonating Apple's crash reporter and leverages the TCC bypass CVE-2020-9771 against macOS Catalina.