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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 wild1

Threat Brief: 3CXDesktopApp Supply Chain Attack (Updated)

Trojanized 3CXDesktopApp installers for Windows and macOS loaded RC4-encrypted shellcode delivering a backdoor to hundreds of thousands of 3CX users.

Threat actors compromised the 3CXDesktopApp build process, adding malicious libraries (ffmpeg.dll, d3dcompiler_47.dll) to installers downloaded from the developer's website. The Windows MSI loader decrypts embedded shellcode with RC4, sleeps for a random 1-4 weeks, then beacons to C2 hidden in icon files on GitHub. Unit 42 fingerprinted 247,277 IPs across 199 countries using 3CX applications and blocked shellcode execution at 127 Cortex XDR customers between March 9-30, 2023.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild1

China-Linked Hackers Exploit Sogou One-Click RCE to Deploy GRAYRABBIT Backdoor

China-linked UNC3569 exploited CVE-2026-51990 in Sogou Input Method to deploy the GRAYRABBIT backdoor in active espionage intrusions.

Gen Threat Labs discovered UNC3569 exploiting CVE-2026-51990, a one-click RCE in Tencent's Sogou Input Method for Windows that chains an insecure sgbiz: protocol handler with an unsandboxed Chromium 80 CEF webview. The chain weaponizes CVE-2021-38003 (V8 type confusion) to run shellcode that DLL-sideloads via 7z.exe/7z.dll and deploys the GRAYRABBIT backdoor, which beacons over RC4-encrypted raw TCP 443 to mail.uaiubifas[.]top. Tencent patched the issue in version 16.3.0.3498, released via automatic updates on April 21, 2026. UNC3569 is a PRC-nexus espionage actor targeting government, education, technology, and financial sectors across East and Southeast Asia.

GBHackersupdated · 2d agofirst · 2d agoThreat actor in the wild 3 sourcesCVE-2026-51990CVE-2021-380031

Four Spy Groups Used the Same Chrome and Windows Exploit Kit Within a Week

Proofpoint links four espionage clusters, including China's APT31, using shared exploit kit BlueMoon chaining Chrome V8 and Windows ALPC zero-days.

Proofpoint reports a previously undocumented exploit kit, BlueMoon, chains Chrome V8 type confusion CVE-2026-85046 with an unassigned V8 sandbox escape and Windows ALPC heap overflow CVE-2026-85880 to achieve code execution and local privilege escalation. APT31 first used it on August 28, 2026 against US NGOs, mining, and commodity trading firms, deploying the GemStone browser backdoor disguised as a Google Gemini extension via the GhostChrome-X integrity bypass. UNK_LateNight, UNK_DoubleCheck, and UNK_QuietRacket followed on September 2-3, targeting US aerospace, Vietnamese manufacturing, and Indonesian/Singaporean sectors with ShadowPad and sideloaded Rust and .NET payloads. Both V8 flaws were patch-gap zero-days, and verbose code suggests possible AI-assisted development.

APT36 Suspected in PATCHCORD Espionage Campaign Using Google Sheets C2

Acronis links the PATCHCORD espionage campaign targeting Afghan telecom and South Asian critical infrastructure to APT36 with moderate confidence.

Acronis Threat Research Unit documented PATCHCORD, a previously undocumented C/C++ backdoor delivered via fake VPN installers impersonating Afghan Telecom (AFTEL), which hijacks Edge, Chrome and Firefox shortcuts for persistence and executes in-memory shellcode. A related Go implant, SHEETCORD, abuses the Google Sheets API for per-victim C2 and was distributed via a domain impersonating India's National Informatics Centre, while a third tool, HACKERAI C2 Agent, uses GitHub Gists and shows signs of LLM-assisted coding. An exposed staging server revealed SuperShell, RAT frameworks, credential-harvesting tools and OpenSSH exploit code, and the researchers attribute the activity to APT36/Transparent Tribe at moderate confidence.

Security Affairs · Aug 16, 2026Threat actor in the wild

One Exploit Chain, Two Espionage Campaigns: Chrome and Windows Under Fire

Two China-linked APT groups reused identical Chrome/Windows zero-day chain against NGOs, deploying GRIMWIDGE backdoor and LONGTALE credential-stealing extension.

Volexity reports that China-linked actors UTA0560 and JungleBamboo (APT31/TA412) ran byte-identical Chrome/Windows exploit chains against NGOs starting September 1, 2026, combining Chrome type confusion CVE-2026-85046, WebAssembly sandbox escape CVE-2026-87491, and Windows kernel flaw CVE-2026-85880. The Chrome bug was fixed in Chromium source but not yet shipped to Chrome users, making it an effective zero-day with an unusual patch gap. UTA0560 delivered the in-memory GRIMWEDGE JScript backdoor, while JungleBamboo deployed the SUPERSTOMP loader installing LONGTALE, a malicious Chrome extension disguised as Google Gemini that steals cookies, session tokens, and keystrokes. Volexity assesses with low confidence the exploit chain was sold or shared among different Chinese end-users.

Security Affairsupdated · 9h agofirst · 1d agoThreat actor in the wild 14 sourcesCVE-2026-85046CVE-2026-87491CVE-2026-858804

Mustang Panda Upgrades CoolClient With a Kernel Rootkit

Mustang Panda's updated CoolClient backdoor deploys a signed kernel driver to hide processes, files and network activity in Asian intrusions.

Kaspersky analysis shows Mustang Panda (HoneyMyte) upgraded its CoolClient espionage backdoor with a signed kernel-mode driver installed as a Windows service, communicating via IOCTL requests to hide processes, files and registry entries. In a Myanmar campaign the actor deployed PlugX first, then CoolClient via a fake Windows Defender directory and Sangfor defender.exe DLL sideloading, with scheduled task and AutoRun persistence and UAC bypass. The updated variant was observed in intrusions across Pakistan, Mongolia and Myanmar, with victims also in Russia including confirmed government entities.

Security Affairs · Aug 16, 2026Threat actor in the wild1

New PATCHCORD Backdoor Targets Afghan Telecom and Indian Critical Infrastructure

Acronis links APT36 (Transparent Tribe) to new backdoors PATCHCORD and SHEETCORD targeting Afghan Telecom and Indian government, defense, and energy networks.

Acronis TRU described an ongoing Pakistan-aligned campaign attributed with moderate confidence to APT36, delivering a previously undocumented C/C++ backdoor named PATCHCORD via fake VPN installers impersonating Afghan Telecom (AFTEL) and telecom management tools. PATCHCORD persists by hijacking browser shortcuts for Chrome, Edge, and Firefox, registers with a single C2 server, and executes shellcode and arbitrary cmd.exe commands. Infrastructure analysis revealed SHEETCORD, a Go backdoor combining SHEETCREEP and PATCHCORD features that uses Google Sheets for C2 and a PowerShell-based remote execution, delivered via a fake site mimicking India's National Informatics Center. APT36 has used PATCHCORD since at least March 2026, including a variant with anti-analysis features used against India's energy sector, and the toolkit includes antnium, GateSentinel, SuperShell, and exploits for CVE-2024-6387.

The Hacker News · Aug 15, 2026Threat actor in the wildCVE-2024-6387