Symantec's Threat Hunter Team detailed a global cyber-espionage campaign by MuddyWater (a.k.a. Seedworm, Static Kitten, Temp Zagros), an APT linked to Iran's Ministry of Intelligence and Security. The group hit at least nine organizations on four continents in Q1 2026 - including a major unnamed South Korean electronics manufacturer where attackers maintained access from February 20 to 27. They abused signed legitimate binaries fmapp.exe (a Fortemedia audio utility) and sentinelmemoryscanner.exe (a SentinelOne component) to sideload malicious DLLs called fmapp.dll and sentinelagentcore.dll, both carrying the ChromElevator post-exploitation tool that lifts data from Chrome-based browsers. Stolen files were staged through public file-transfer service sendit[.]sh to blend in.
ReliaQuest researchers say initial access broker KongTuke has shifted from web-based ClickFix and FileFix lures to Microsoft Teams social engineering, taking as little as five minutes to gain persistent access. The attacker reaches employees from one of five rotating Microsoft 365 tenants, uses Unicode whitespace tricks to make the display name look like internal IT help desk, then talks the victim through pasting a PowerShell command. That command downloads a ZIP from Dropbox containing a portable WinPython runtime and a Python-based RAT called ModeloRAT. The new ModeloRAT variant adds a five-server C2 pool with automatic failover, self-update, and randomized URL paths, and several major EDR products did not detect it.
Bitdefender researchers documented a China-linked espionage group called FamousSparrow repeatedly compromising an Azerbaijani oil and gas company between late December 2025 and late February 2026. Each time the victim cleaned up, the attackers came back through the same unpatched Microsoft Exchange Server and dropped a new backdoor - first Deed RAT (a ShadowPad relative used by several Chinese groups), then TernDoor. The group overlaps with the Earth Estries cluster, which itself overlaps with Salt Typhoon. This is the first time FamousSparrow has been seen targeting South Caucasus energy infrastructure, a region whose role in supplying gas to Europe grew sharply after Russia's Ukraine transit deal expired.
Socket researchers found more than 150 RubyGems packages doing something the registry was never built to do: smuggling scraped data out of UK council websites. The malicious gems fetch pages from Lambeth, Wandsworth, and Southwark's public meeting portals, bundle the responses into a normal-looking .gem archive, and push it back to RubyGems using a hardcoded API key. The attacker then downloads the data as a public gem version. Whether GemStuffer is registry spam, a worm being tested, or a deliberate trial of package-registry abuse, the mechanics are intentional - and it landed the same week RubyGems froze new account signups over a separate flood of malicious packages.
The Gentlemen, the second most prolific public ransomware operation of 2026 with over 320 listed victims, has had its own internal database leaked. Check Point Research and others obtained the data after a breach of the group's hosting provider 4VPS exposed their Rocket backend. The leak unmasks roughly 9 named operators centered on an administrator known as zeta88 (aka hastalamuerte), who built the RaaS panel in three days using DeepSeek and Qwen AI coding assistants, runs payouts, and joins encryption events personally. Internal chats also confirm chain-victimization: in April the group hit a UK software consultancy and then weaponized stolen client credentials to compromise one of the consultancy's customers in Turkey.
TeamPCP launched its largest supply-chain attack to date on May 11, compromising 170+ npm and PyPI packages with 518 million combined weekly downloads. The attackers chained three GitHub Actions vulnerabilities to publish 401 malicious versions carrying valid SLSA Build Level 3 attestations - cryptographically indistinguishable from legitimate releases. Affected packages include TanStack, Mistral AI (npm and PyPI), UiPath, OpenSearch, and Guardrails AI. The worm installs a persistent gh-token-monitor daemon that triggers 'rm -rf ~/' if tokens get revoked, and includes a probabilistic full-disk-wipe routine for Israeli and Iranian locales.
TeamPCP, the group behind the March Trivy breach and Shai-Hulud npm worm, used credentials stolen in that March attack to publish a backdoored version of Checkmarx's Jenkins AST plugin to the Jenkins Marketplace. This is the third Checkmarx supply-chain hit since late March. The rogue version 2026.5.09 went up on May 9, outside Checkmarx's normal release process - no git tag, no GitHub release. Checkmarx says its GitHub repos are isolated from customer production and no customer data is stored there, but anyone who installed the bad plugin should assume their CI credentials are compromised, rotate them all, and hunt for lateral movement.
The TrickMo Android banking malware now routes its command-and-control through The Open Network (TON), the decentralized peer-to-peer network originally built around Telegram, making the C2 infrastructure much harder to identify or take down. ThreatFabric (which tracks this variant as Trickmo.C) has been watching it since January in campaigns hitting users in France, Italy, and Austria. The malware disguises itself as TikTok or streaming apps and steals banking credentials and crypto wallet keys via phishing overlays, keylogging, SMS interception, OTP suppression, and live screen recording. The new variant also adds SSH tunneling, port forwarding, and SOCKS5 proxy commands, turning infected phones into a pivot point.
A researcher at Israel Aerospace Industries published a proof-of-concept tool called GhostLock that uses a legitimate Windows API call to make files unreadable without encrypting anything. The technique abuses the dwShareMode parameter of CreateFileW - setting it to 0 grants the calling process exclusive access, so every other user or app trying to open the file gets a sharing violation. GhostLock automates this recursively across SMB shares from a standard domain user account, no elevation required. Researcher Kim Dvash frames it as a disruption attack, not destructive - data is not lost, but operational downtime can mirror a ransomware incident.
QiAnXin XLab has tied the ongoing exploitation of cPanel's CVE-2026-41940 to a previously-quiet threat actor it tracks as Mr_Rot13, who has been operating since at least 2020. The attack chain exploits the cPanel and WHM authentication bypass to drop a Go-based infector that adds an attacker SSH key, plants a PHP web shell, and serves a fake login page to steal cPanel credentials (ROT13-encoded, exfiltrated to wrned[.]com). The final payload is a cross-platform backdoor called Filemanager that runs on Windows, macOS, and Linux. XLab counts over 2,000 attacker source IPs currently scanning for this flaw.
TrustStrike Labs