Angry Birds: Toy Ghouls’ new toys
Kaspersky tracks ransomware group Toy Ghouls deploying new custom backdoors, mqtt-bird-agent and matrix-bird-agent, using HiveMQ MQTT and Element as C2 channels.
Kaspersky reports that Toy Ghouls (also known as Bearlyfy, Laboo.boo and Feral Wolf), a financially motivated group targeting Russian organizations since 2025, shifted from leaked Babuk and LockBit builders and public GitHub tools to its custom GenieLocker ransomware. In early July 2026 the group deployed two custom backdoors: mqtt-bird-agent 0.1.0 using the public HiveMQ MQTT broker as C2, and matrix-bird-agent 0.1.0 using the Element messenger. The backdoors are delivered via WinRM using Evil-WinRM and WinRM-fs, persist as Windows services, and encrypt their configuration with ChaCha20-Poly1305 keyed to the machine's MachineGuid registry value.
PAPERMILL Hackers Abuse Signed Notepad++ to Deploy VenomRAT in Tax Audit Attacks
PAPERMILL phishing campaign abuses a signed Notepad++ copy and tax-audit lures to deploy VenomRAT against targets in India.
JUMPSEC tracks PAPERMILL as an emerging cluster whose emails pass SPF, DKIM, and DMARC and deliver tax-audit themed disk images. The mounted image pairs a legitimately signed, renamed executable with a rogue libcurl.dll for DLL sideloading, then uses a Donut shellcode loader to run VenomRAT 6.0.3 in memory with hidden VNC, data-stealing, and file-grabbing capabilities. The loader includes anti-analysis checks and RunOnce persistence, and lures plus China-connected infrastructure overlap with the Silver Fox ecosystem, though attribution remains unconfirmed.
SloppyRAT: A New Tool For Ransomware Attacks
Zscaler details SloppyRAT, a new DLL backdoor delivered via ClickFix lures that stages CastleLoader and CastleRAT ahead of ransomware attacks.
Zscaler ThreatLabz analyzed SloppyRAT, a DLL-based backdoor distributed via ClickFix lures that abuses finger.exe over TCP port 79 to download a batch script. The malware copies curl.exe to download IronPython 3.4.2 from GitHub and executes zlib-compressed Base64-encoded Python to deploy CastleLoader and CastleRAT, then reflectively loads SloppyRAT in memory. It hinders analysis using XOR stack-string obfuscation, a modified affine cipher with modulus 127, and 13 runtime-decrypted code blocks, while communicating with C2 over a reverse SOCKS channel.
Fake Claude Opus 5 app delivers malware and wipes its own tracks
A fake 'Claude Opus 5' GitHub repository impersonating Anthropic distributes RevStealer, a Windows infostealer stealing passwords, crypto wallets and VPN credentials.
Morphisec identified a malicious GitHub repository, Claude-Opus-5-Free-Desktop, impersonating Anthropic to distribute a roughly 101 MB download that launches RevStealer, a Windows information-stealing malware. The malware targets browser credentials, Windows Credential Manager, a dozen password managers, more than fifty cryptocurrency wallets, VPN, messaging, game launcher and streaming accounts, streaming stolen data to its server before deleting itself. It evades analysis with ten sandbox and VM checks, indirect system calls, Windows Defender exclusions, a fake verification window, and a Polygon blockchain smart contract fallback for C2. Only 1 of 66 antivirus engines flagged the sample at check time.