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Multiple ArtraDownloader Variants Used by BITTER to Target Pakistan

BITTER used three ArtraDownloader variants since 2015 to target Pakistan, China, and Saudi Arabia, deploying BitterRAT and exploiting CVE-2017-11882 in one wave.

Palo Alto Unit 42 documents ArtraDownloader, a previously unreported downloader family used by the suspected South Asian group BITTER, with three variants and roughly 80 unique samples dating back to February 2015. Between September 2018 and January 2019, BITTER used spearphishing documents hosted on compromised Pakistani websites to target Pakistan and, for the first time, Saudi Arabia; one RTF sample exploited the EQNEDT vulnerability CVE-2017-11882. The downloader retrieves BitterRAT over HTTP, uses simple registry keys for persistence, and byte-level string obfuscation. Infrastructure overlap with the previously reported MY24 InPage-exploit payload was also observed.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wildCVE-2017-11882

Tick Group Weaponized Secure USB Drives to Target Air

Unit 42 says the Tick group weaponized South Korean certified secure USB drives with SymonLoader malware to reach air-gapped Windows XP systems.

Unit 42 discovered that the Tick cyberespionage group, which targets Japan and South Korea, compromised an ITSCC-certified secure USB drive made by a South Korean defense company and used a new loader named SymonLoader to extract a hidden executable from these drives. SymonLoader only infects Windows XP and Windows Server 2003, suggesting deliberate targeting of legacy air-gapped systems used by government and defense organizations. The group also delivered HomamDownloader and SymonLoader via Trojanized Korean and Japanese software sent as spearphishing attachments. Unit 42 believes the attacks occurred multiple years ago and that this malware is not part of an active campaign.

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

RANCOR: Targeted Attacks in South East Asia Using PLAINTEE and DDKONG Malware Families

Unit 42 names RANCOR, a previously unidentified espionage group targeting Southeast Asian political entities with newly discovered PLAINTEE and DDKONG malware families.

Unit 42 tracks a previously unidentified group it dubs RANCOR conducting highly targeted espionage attacks in Singapore and Cambodia using two custom malware families, DDKONG and PLAINTEE. Attacks appear to have begun with spear phishing, with decoy political news documents hosted on legitimate sites including a Cambodian government website and Facebook. Infrastructure links to IP 89.46.222[.]97 and KHRAT-associated domains such as facebook-apps[.]com, and the activity is grouped into two clusters tied together by PLAINTEE usage and similar targeting.

Palo Alto Unit 42 · Aug 17, 2026Threat actor1

Aggah Campaign: Bit.ly, BlogSpot, and Pastebin Used for C2 in Large Scale Campaign

Aggah campaign abuses Bit.ly, BlogSpot, and Pastebin as multi-hop C2 to deliver RevengeRAT across the Middle East, US, Europe, and Asia.

Unit 42 details the Aggah campaign, which began with spearphishing emails in March 2019 spoofing a large financial institution and targeting education, media/marketing, and government organizations in the Middle East, later expanding to the US, Europe, and Asia. Delivery documents use Template Injection to load a remote OLE file whose macro runs mshta against a Bit.ly link redirecting to a BlogSpot post, which then uses Pastebin pastes to download RevengeRAT configured with a duckdns[.]org C2 domain. The embedded script also deletes Microsoft Defender signatures and kills Defender and Office processes, and modifies registry keys to enable macros. High-level TTPs resemble the Gorgon Group, but Unit 42 could not confirm attribution.

Palo Alto Unit 42 · Aug 17, 2026Threat actor

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

New Malware 'Rover' Targets Indian Ambassador to Afghanistan

Unit 42 reports a spearphishing attack delivering the custom Rover Trojan to India's Ambassador to Afghanistan, exploiting CVE-2010-3333 in Word.

On December 24, 2015, Unit 42 identified a targeted spearphishing email spoofing Indian Defence Minister Manohar Parrikar, sent to India's Ambassador to Afghanistan. The RTF attachment exploited CVE-2010-3333 in Microsoft Word to download a downloader from newsumbrella.net, which retrieved the Rover Trojan and DLL plugins from 46.166.165.254. Rover uses OpenCV for webcam capture, OpenAL for audio recording and libsndfile for audio files, with data exfiltration over its C2 channel; separate payload versions target Windows XP and later systems.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wildCVE-2010-3333

xHunt Campaign: Attacks on Kuwait Shipping and Transportation Organizations

xHunt deployed custom backdoors Hisoka, Killua, Gon, and EYE against Kuwait shipping and transportation organizations, using DNS tunneling and email-draft C2 channels.

Unit 42 observed the xHunt campaign targeting Kuwait transportation and shipping organizations between May and June 2019, installing backdoors named after characters from the anime Hunter x Hunter, including Hisoka, Killua, Sakabota, and Netero. The tools use HTTP and DNS tunneling for C2, and Hisoka v0.9 added an unusual email-based C2 channel that abuses Exchange Web Services with stolen credentials to exchange email drafts. The Gon tool provides port scanning, file transfer, screenshots, remote command execution, and RDP session creation, while EYE acts as a cleanup failsafe if a legitimate user logs in. Related activity targeting Kuwait between July and December 2018 was reported by IBM X-Force IRIS, suggesting the campaigns are likely related.

Palo Alto Unit 42 · Aug 17, 2026Threat actor1

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

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 · Aug 17, 2026Threat actor