Impersonating IT support: how threat actors turn a remote session into enterprise-wide access
Microsoft details Teams IT-support impersonation campaigns deploying Node.js implants, AD reconnaissance, and WinRM lateral movement toward domain controllers.
Microsoft Threat Intelligence describes a human-operated campaign where attackers impersonate IT/helpdesk staff via Microsoft Teams external collaboration, talk users into granting remote sessions, and use RMM tools for interactive access. During the session they run PowerShell to silently install a malicious MSI that stages a portable Node.js runtime and obfuscated JavaScript implant for C2, executing follow-on payloads via rundll32. Operators then perform host and Active Directory reconnaissance, capture desktop screenshots, and pivot via WinRM on port 5985 to domain controllers and certificate authorities. The hands-on-keyboard chain, which can precede data theft and ransomware, blends into normal operations by relying on Teams, Quick Assist, msiexec, and Node.js; Microsoft shares hunting and mitigation guidance.
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.
FamousSparrow Exploits Public-Facing Exchange Servers to Deploy SparroWocky Backdoor
ESET attributes a new SparroWocky backdoor to espionage group FamousSparrow, deployed via exploited internet-facing Exchange servers across Latin American governments.
ESET's Welivesecurity team reports FamousSparrow gained initial access by exploiting publicly reachable Microsoft Exchange servers, with roughly 90 percent of targets since mid-2025 in Latin America, including governments in Argentina, Ecuador, Guatemala, Honduras, Panama, Peru, Puerto Rico, and Venezuela. The group's new modular C-language backdoor SparroWocky replaces SparrowDoor and uses a three-part loader: a legitimate executable, a malicious DLL side-loaded in memory, and an encrypted payload. It persists via Windows services or Registry Run keys, supports screenshots, file operations, TCP proxying, Beacon Object Files, TLS/RC4-encrypted C2, and anti-forensics such as call-stack spoofing. IOCs including loader SHA-1 hashes and C2 IP addresses were published.
TrueConf Server Flaws Exploited to Replace Client Installers with PhantomCore
Head Mare exploits TrueConf server flaws to install web shells and deliver PhantomCore and PhantomGraph backdoors at Russian organizations.
Kaspersky detected July 2026 attacks by the threat actor Head Mare exploiting a vulnerability chain (KLCERT-26-057 and KLCERT-26-058) in unpatched TrueConf videoconferencing servers. The chain enables arbitrary code execution with SYSTEM privileges, deployment of a web shell at locale.php, and replacement of client installers with versions delivering the PhantomCore backdoor and PhantomGraph, which uses Microsoft OneDrive as C2. Targets span Russian instrumentation, electronics, transport, energy, IT, and software firms. Patches shipped in TrueConf Server 5.3.9, 5.4.9, and 5.5.5 on June 18, 2026.
Silver Fox Targets Japanese Manufacturer with 3
Chinese group Silver Fox used new vulnerable drivers and DLL side-loading to deploy ValleyRAT at a Japanese industrial manufacturer.
Cato Networks detailed a Silver Fox campaign against a Japanese industrial manufacturing organization combining new vulnerable-driver abuse (BootRepair.sys and EnPortv.sys alongside wsftprm.sys), DLL side-loading via Zeon Corporation PDF binaries, and NTDLL unhooking to deliver ValleyRAT (Winos 4.0), a Gh0st RAT variant. The chain starts with an invoice-themed phishing lure hosting attacker-controlled content on legitimate QQ and Tencent Cloud services. Shellcode is injected into svchost.exe via thread-context hijacking, and a dual watchdog design pairs payload monitoring with a scheduled-task batch script for persistence. A separate 180-day VirusTotal retrohunt found 146 Atlas RAT samples across six PDB builds, though the Silver Fox link remains circumstantial.
Russia-Aligned Hackers Use GuardBreaker Prompt Injection to Disrupt AI Malware Analysis
Russia-aligned group UAC-0099 embeds GuardBreaker prompt injection in a VBScript comment to make AI malware scanners refuse analysis of a MATCHBOIL loader.
ESET identified a UAC-0099 VBScript used in an early-stage intrusion against a target in Ukraine that hides a safety-triggering comment (a question about building a nuclear weapon) intended to make AI code scanners refuse to continue analysis. The script downloads MATCHBOIL, a loader associated exclusively with UAC-0099, alongside familiar anti-analysis checks for IDA and Wireshark. The technique turns the AI triage process itself into the attack target, risking missed detections or benign misclassification of malicious samples.
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.
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.