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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

Agents Gone Wild: An AI-Orchestrated Global Campaign Against PaperCut NG/MF

AI-orchestrated campaign exploited PaperCut NG/MF RCE (CVE-2026-81578/82078), compromising 440+ instances at 395 organizations in 48 countries.

GreyNoise tracked a likely Russian-speaking actor using AI (OpenAI Codex harness plus a DeepSeek model) to develop, test, and deploy exploits for PaperCut NG/MF (CVE-2026-81578, CVE-2026-82078) starting 31 August 2026. The actor compromised at least 440 PaperCut instances across 395 organizations in 48 countries, achieving domain admin at 12 victims — fastest time to domain admin was five minutes and a US high school was fully compromised in seven minutes. Attack paths involved LSASS memory and registry secret harvesting, pass-the-hash to domain controllers, noPac attacks, account additions to Domain Admins, and DCSync to exfiltrate full NTDS.DIT credential dumps. Impact scope suggests access development potentially for handoff, with prior PaperCut intrusions historically leading to extortion.

GreyNoise · 8d agoThreat actor in the wildCVE-2026-81578CVE-2026-82078CVE-2021-42278+1 CVEs1

Threat Brief: Ongoing Russia and Ukraine Cyber Activity

Ukrainian government sites were defaced via OctoberCMS CVE-2021-32648 while Microsoft-attributed actor DEV-0586 deployed destructive WhisperGate malware.

Unit 42 tracks January 2022 attacks against Ukrainian government websites that were defaced or made inaccessible, which Ukraine attributed to Russia. Attackers exploited CVE-2021-32648, an account takeover flaw in OctoberCMS prior to 1.0.472, by submitting a boolean true as the password reset code to bypass validation. Separately, WhisperGate malware, attributed by Microsoft to DEV-0586, disabled Windows Defender and corrupted files across multiple Ukrainian organizations, using a ransomware-appearing first stage and an HTTPS-beaconing second stage with LOLBINs and anti-analysis techniques.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wildCVE-2021-326481

Mustang Panda Adds Signed Windows Rootkit to CoolClient Backdoor for Stealth

Kaspersky reports Mustang Panda's updated CoolClient backdoor now deploys a signed kernel-mode Windows rootkit, hitting government victims in Myanmar, Mongolia, Pakistan, and Russia.

Kaspersky identified a new CoolClient variant attributed to HoneyMyte (Mustang Panda) that installs a digitally signed Windows kernel driver, msagent.sys, to hide and protect malicious processes, files, registry keys, and C2 network information. CoolClient is consistently deployed as a secondary backdoor after PlugX, with confirmed victims including government entities in Myanmar, Mongolia, Pakistan, and Russia. In a Myanmar campaign, PlugX was used to deploy CoolClient via a renamed Sangfor executable for DLL side-loading, a scheduled task for persistence, and RPC-based process creation with PPID spoofing. The driver, signed with a 2013 certificate issued to Nanjing Ranyi Technology, implements 33 IOCTL handlers, process hiding via unlinking, a filesystem minifilter, and registry callbacks.

The Hacker News · Aug 15, 2026Threat actor in the wild1

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.

The Hacker News · 7d agoThreat actor in the wild 2 sourcesCVE-2026-85046CVE-2026-858801

Counterfeit installers to system compromise: Tracking a deceptive software download campaign

Microsoft tracks a counterfeit software-installer campaign compromising multinationals' China operations, moderately linked to the Silver Fox (Yinhu) actor.

Microsoft Defender Experts is tracking an active campaign using spoofed software download sites for brands such as Razer, Kaspersky, Microsoft Edge, Calibre, and Baidu Netdisk on .com.cn and .hl.cn domains, delivering installer archives whose hashes change per download, indicating server-side payload generation. The implants establish persistence, weaken security protections, and communicate with attacker-controlled infrastructure, with confirmed compromises across healthcare, manufacturing, gaming, technology, logistics, government, and education. Microsoft assesses with moderate confidence that the activity matches the publicly reported Silver Fox (Yinhu) fake software campaign; it has not attributed it to a nation-state actor.

Microsoft Security Blog · 15d agoThreat actor in the wild1

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

North Korean Lazarus Group Uses Windows Zero

Check Point links Lazarus Group's Operation Dream Job to a new Windows zero-day, CVE-2026-68820, targeting defense workers with fake Lockheed Martin job offers.

Check Point Research documented a new wave of Operation Dream Job, a North Korean Lazarus Group campaign targeting defense and aerospace professionals in France, Germany, Brazil, and India with fake Lockheed Martin job offers. The attacks chain a previously unknown Windows privilege escalation flaw in AFD.sys, CVE-2026-68820, which Microsoft patched on August 11, 2026, to deploy the MISTPEN downloader, ForestTiger backdoor, and updated FudModule 3.1 kernel rootkit. Check Point also discovered a new Troy backdoor DLL with 17 operator commands and a RelayShell PHP webshell deployed on compromised Roundcube and WordPress servers used as command relays, some infected via CVE-2025-49113 or leaked credentials. Defenders are urged to apply the August 2026 Patch Tuesday update and review Check Point's indicators of compromise.

Security Affairs · Aug 13, 2026Threat actor in the wildCVE-2026-68820CVE-2025-491131

Lazarus hackers pair fake job offers with Windows zero-day exploit

Lazarus' Operation Dream Job targets the defense sector with fake job offers, a Windows LPE zero-day (CVE-2026-68820), and new Troy and RelayShell backdoors.

Check Point documented two parallel infection chains in Lazarus' Operation Dream Job: a digitally signed PDF viewer with DLL sideloading delivering the MISTPEN in-memory downloader, and a trojanized SecurityPDF viewer, distributed via fake Enveil websites, installing the newly documented Troy backdoor. A component exploits CVE-2026-68820, a local privilege escalation zero-day in the Windows AFD.sys driver used since at least early July, which Microsoft patched on August 11, 2026, enabling deployment of the FudModule kernel-mode rootkit. Lazarus also compromised Roundcube webmail servers vulnerable to CVE-2025-49113 to deploy the RelayShell PHP web shell and relay C2 traffic, targeting defense-sector organizations primarily in Western Europe and India. Separately, CERT-UA documented Sandworm's UAC-0145 using fake job offers against IT professionals since May 2026.

Help Net Security · Aug 12, 2026Threat actor in the wildCVE-2026-68820CVE-2025-49113

Iranian hackers use CHOSEN BRICK Windows malware to spy on targets

Iranian state-linked hackers use CHOSEN BRICK Windows malware, spread via Telegram and WhatsApp social engineering, to spy on dissidents and journalists worldwide.

US, UK, and Dutch cyber agencies with the FBI issued a joint advisory on Iranian state-linked hackers deploying a Windows malware strain called CHOSEN BRICK against dissidents, activists, and journalists, primarily in the US, UK, and Netherlands. Attacks begin with messages on WhatsApp or Telegram impersonating trusted contacts or technical support, tricking victims into running malicious files disguised as apps such as Pictory, RunwayML, Norton Antivirus, Telegram, and KeePass. The malware persists via Registry Run keys, adds Microsoft Defender exclusions, and uses a per-victim Telegram bot for command-and-control while stealing email, Telegram and WhatsApp data, screenshots, and audio. Stolen data is exfiltrated via Telegram or cloud services like VultrObjects and StorjShare, and sometimes appears on pro-Iranian leak sites, increasing physical risk for dissidents abroad.

BleepingComputerupdated · 1h agofirst · 18h agoThreat actor in the wild 9 sources

Iranian cyber targeting of dissidents, activists and journalists

UK NCSC, FBI, and Dutch AIVD expose CHOSEN BRICK spyware used by Iranian state actors against dissidents, activists, and journalists worldwide.

A joint advisory from the UK NCSC, FBI, and Dutch AIVD details CHOSEN BRICK, a Windows spyware family used by Iranian state cyber actors since at least 2025 against dissidents, activists, and journalists in the UK, US, and Netherlands. Actors build rapport on WhatsApp and Telegram impersonating known contacts or platform support, then deliver disguised payloads resembling apps such as Telegram, Norton, RunwayML, or fake MRI results. The malware persists via HKCU Run registry keys, adds Microsoft Defender exclusions, and uses a unique Telegram bot C2 per victim. Capabilities include screen capture, microphone recording, process enumeration, email and messaging data theft, file deletion, and system wiping; victim data has appeared on pro-Iranian leak sites.

NCSC UK · 2d agoThreat actor in the wild2

ThreatsDay: CEO Phishing Kits, 5K Dropbox Account Hacks, OAuth Traps + 17 More Stories

Microsoft warns of Teams IT-impersonation intrusions deploying Node.js implants; Spring Ring vishing hit 150+ employees across 10 companies; The Gentlemen ransomware claims 683 victims.

Microsoft warned of a human-operated campaign abusing Teams external collaboration to impersonate IT help desk staff, deploy malicious MSI packages staging Node.js runtimes and obfuscated JavaScript implants, then pivot to domain controllers over WinRM. Unit 42 documented the Spring Ring vishing operation targeting over 150 employees across at least 10 companies using 26 attacker identities, including an NTLM relay variant against domain controllers. Sophos reported The Gentlemen ransomware (Gold Sherwood) reached 683 total victims by end of July 2026, adding 169 in July, with a playbook using BYOVD-based EDR killers and backup tampering. Group-IB found the Outsider phishing-as-a-service platform created 700+ new phishing pages within a month despite law enforcement takedowns.

The Hacker News · 13d agoThreat actor in the wild1

Lazarus Exploits Windows Zero-Day to Gain SYSTEM Access and Deploy Backdoor

Lazarus exploits Windows AFD.sys zero-day CVE-2026-68820 in Operation Dream Job to deploy Troy backdoor at defense firms.

Check Point attributes Operation Dream Job attacks to Lazarus Group exploiting CVE-2026-68820 (CVSS 7.0), a privilege escalation flaw in Windows AFD.sys patched in August 2026 Patch Tuesday. The campaign targets defense and aerospace firms in France, Germany, Brazil, and India via trojanized PDF viewers and DLL side-loading, deploying backdoors Troy, ForestTiger, and the FudModule 3.1 kernel rootkit. Attackers also compromise WordPress, SharePoint, and Roundcube servers as C2, using CVE-2025-49113 and the RelayShell PHP web shell.

The Hacker News · Aug 15, 2026Threat actor in the wildCVE-2026-68820CVE-2025-491132

Three Threat Groups Target Russian Enterprises With Backdoors, Ransomware, and Wipers

Kaspersky details NightEagle, Hacking Cat, and Toy Ghouls targeting Russian enterprises with Exchange backdoors, Gorilla RAT, and destructive Monkey ransomware.

Kaspersky reports three threat clusters targeting Russian enterprises: NightEagle (APT-Q-95), the pro-Ukrainian hacktivist group Hacking Cat, and Toy Ghouls. NightEagle uses compromised VPN credentials and the GhostContainer modular backdoor to fully compromise Microsoft Exchange servers, chaining CVE-2020-0688 exploitation, BlueKeep (CVE-2019-0708), Active Directory vulnerabilities, and DCSync to seize domain controllers. Hacking Cat exploits Exchange flaws including CVE-2021-26855 and CVE-2026-42897 to deliver the Gorilla RAT and multiple Monkey ransomware variants written in Rust, .NET, C++, and Golang targeting Windows, Linux, and VMware ESXi, with some variants acting as wipers that never store the encryption key.

The Hacker Newsupdated · 6h agofirst · 23h agoThreat actor in the wild 5 sourcesCVE-2020-0688CVE-2019-0708CVE-2021-26855+1 CVEs2

Iranian spies hit Windows machines with Chosen Brick data-stealing malware

FBI, UK NCSC, and Dutch AIVD warn Iranian intelligence uses Chosen Brick spyware against dissidents, stealing contacts, emails, and messaging data.

A joint advisory from the FBI, UK NCSC, and Dutch AIVD says Iranian state cyber actors have used the Chosen Brick Windows malware since at least 2025 to surveil dissidents, activists, and journalists. Attacks begin with heavily researched WhatsApp and Telegram messages impersonating trusted contacts, tricking victims into opening fake installers resembling Pictory, RunwayML, Norton Antivirus, Telegram, Adobe Flash Player, and KeePass. The malware persists via the HKCU Run registry key, adds Microsoft Defender exclusions, uses victim-specific Telegram bots for C2, captures screen and audio, steals emails and Telegram/WhatsApp data, and can wipe systems.

The Register · Security · 1d agoThreat actor in the wild1

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 · 2h agofirst · 2d agoThreat actor in the wild 13 sourcesCVE-2026-85046CVE-2026-87491CVE-2026-858804

Attackers Expose Ongoing AI Tool Use Targeting Organizations in Latin America

Unit 42 documents two AI-assisted intrusion campaigns against Latin American government, utility, and financial organizations using LLM-orchestrated tooling.

Palo Alto Networks Unit 42 tracks two ongoing intrusion clusters, CL-CRI-1131 (Mexican transportation, federal ministries, municipal water utilities) and CL-CRI-1163 (Brazilian financial sector), both using living-off-the-land techniques, SOCKS5 relays, and custom RATs. The attackers appear to orchestrate operations via commercial LLMs like Claude and GPT-4.1, evidenced by iterative batch scripts and AI-generated tunneling tool naming. The Mexican campaign (also reported as Operation Escaneo by CloudSEK) exfiltrated sensitive data via dynamic-DNS infrastructure with rotated multi-SAN TLS certificates between February and June 2026. This signals broader adoption of AI-enhanced operations by diverse threat groups in the region.

Palo Alto Unit 42 · 14d agoThreat actor in the wild1