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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.

Zscaler ThreatLabzupdated · 5d agofirst · 5d agoMalware in the wild 3 sources

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.

CISA Advisories · 6d agoAdvisoryCVE-2026-87020

xHunt Campaign: New PowerShell Backdoor Blocked Through DNS Tunnel Detection

xHunt's new CASHY200 PowerShell backdoor used DNS tunneling for C2; DNS security blocked beaconing at a Kuwait organization in September 2019.

Unit 42 describes CASHY200, a new PowerShell-based backdoor tied to the xHunt campaign that communicates with its C2 server windows64x[.]com via DNS tunneling, parsing commands from DNS answers. In September 2019, a Kuwait-based organization's DNS security service blocked the beaconing minutes after detection, cutting off adversary access. Samples dating to May and June 2018 and open source collection suggest the tool was used against Kuwait government organizations from spring 2018 through 2019, with malicious Word documents observed installing CASHY200 payloads configured with C2 domains such as firewallsupports[.]com and winx64-microsoft[.]com. The tool's name derives from identifiers stored under the registry key HKCU\Software\Microsoft\Cashe and the command value 200.

Palo Alto Unit 42 · 29d agoThreat actor

MILE TEA: Cyber Espionage Campaign Targets Asia Pacific Businesses and Government Agencies

Unit 42 names MILE TEA, a cyber-espionage campaign since 2011 targeting Japanese and Taiwanese businesses and government agencies with e-ticket phishing lures and Elirks-family malware.

Unit 42 tracks the MILE TEA espionage campaign, observed as early as 2011, targeting Japanese trading, petroleum, and mobile companies, a Beijing office of a Japanese public organization, and a Taiwanese government agency. The primary infection vector is spear-phishing emails with attachments, mostly custom executable installers posing as flight e-tickets, dropping Elirks, Micrass, or Logedrut as initial bridgehead malware. Elirks and Logedrut retrieve encrypted C2 addresses from attacker-posted blog articles, decoded with Base64 and TEA or DES ciphers. The campaign's focus shifted from Taiwan to Japan around 2013.

Palo Alto Unit 42 · 29d agoThreat actor in the wild1

Fwd: XZ Utils 5.8.4 and a security fix

XZ Utils 5.8.4 fixes an invalid memory write that occurs when a decoder is reinitialized after allocation failure in 5.8.3 and older.

XZ Utils 5.8.4 has been released with a security fix for versions 5.8.3 and older. The flaw is an invalid memory write that can occur when a decoder is reinitialized after an allocation failure. The announcement was posted on the oss-security mailing list by Sam James pointing to the upstream stable release. Users and distributions running affected versions should upgrade to 5.8.4.

oss-security · 6d agoVulnerability

USN-8716-2: FFmpeg vulnerabilities

Ubuntu issued USN-8716-2 fixing FFmpeg VobSub, Vulkan HEVC, and NVDEC decoder flaws that could allow denial of service or code execution.

USN-8716-2 provides the Ubuntu 26.04 LTS counterpart to the FFmpeg fixes in USN-8716-1. Crafted media files could cause denial of service or arbitrary code execution through the VobSub subtitle demuxer (CVE-2026-64830), the Vulkan HEVC hardware decoder (CVE-2026-64831), and the NVDEC video decoder path.

Ubuntu Security Noticesupdated · 5d agofirst · 6d agoAdvisory 13 sourcesCVE-2026-64830CVE-2026-64831

Fake OpenAI Codex download tricks macOS users into installing malware

Cato Networks uncovered a malware campaign using sponsored search ads and fake OpenAI Codex pages to deliver an AMOS-like infostealer to macOS users.

Cato Networks researchers discovered a campaign using sponsored search results and a fake OpenAI Codex download portal on Google Sites to lure macOS users. Victims are instructed to paste a Terminal command that decodes a Base64-encoded URL and runs a multi-stage infection chain ending in a universal Mach-O binary. The delivery chain closely resembles Atomic macOS Stealer (AMOS), and related infrastructure impersonating Claude Code was also found. Operators use iframe-based hosting and path/device gating to evade analysts and automated scanners.

Help Net Security · 22d agoMalware in the wild

Stately Taurus Activity in Southeast Asia Links to Bookworm Malware

Unit 42 links Stately Taurus APT activity in ASEAN region and Myanmar to the decade-old Bookworm malware family via infrastructure overlaps.

Unit 42 connected Stately Taurus (aka Mustang Panda) espionage activity targeting ASEAN-affiliated organizations and Myanmar to the Bookworm malware family, first published in 2015. Earlier attacks delivered the PubLoad stager via DLL sideloading, with a PubLoad variant communicating with C2 at 123.253.32[.]15 while mimicking Windows Update URLs. Three previously unreported loader samples from 2021-2022 used UUID-decoded shellcode loaded via heap allocation and API callbacks, ultimately decrypting and loading Bookworm DLLs. A ToneShell backdoor variant shared debug paths with Bookworm loaders, and the January 2024 CSIRT CTI post corroborated the Myanmar attacks.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild