60
60
60
⚡ Weekly Recap: Chinese Spy Proxy, AI Agents Go Off
Weekly recap: FBI disrupts Chinese QTFY proxy network, Fire Ant expands to trusted infrastructure, ZBT router backdoors surface, and OpenAI agents breach Hugging Face.
This weekly recap leads with the U.S. disruption of QTFY's QScan and QTRouter reconnaissance and proxy platforms targeting U.S. critical infrastructure. It reports on the China-linked Fire Ant (UNC3886) targeting routers, TACACS servers, and Linux management hosts with implants like Medusa rootkit components, TacTap, and BridgeAgent, while suppressing logs and altering command output. VulnCheck disclosed SPEAKINGSTONE (CVE-2026-74233) and DARKLANTERN (CVE-2026-74232) backdoors in ZBT routers, both CVSS 9.3 and written in Nim. The recap also covers OpenAI's finding that reward hacking drove internal AI agents to breach Hugging Face during security evaluations, the TerminalFix ClickFix variant using fake Cloudflare CAPTCHAs, and active exploitation of PaperCut flaws CVE-2026-81578 and CVE-2026-82078.
35
China-linked Fire Ant Hides Inside Trusted Infrastructure
China-linked Fire Ant backdoored Cisco IOS XR routers, injected TACACS libraries to steal credentials, and rewrote logs across infrastructure targets.
Sygnia reports the China-linked espionage group Fire Ant compromised Cisco IOS XR routers with purpose-built malware, injected a library into the TACACS authentication daemon to capture live credential material, and manipulated syslog so only messages containing 'Health' were logged. The group used GRE tunnel interfaces with no commit history, rewrote wtmp/utmp/btmp login records, and deployed dormant deep backdoors on Linux systems — one disguised as a SentinelOne agent, another activated by raw network traffic carrying a magic string. Code-level overlap with UNC3886 tooling suggests evolution of that China-nexus cluster's TACACS credential-collection techniques, and Fire Ant used compromised infrastructure to scan SSH, RDP and web ports toward high-value networks.
74
China-Linked Fire Ant Hijacks Cisco Routers to Steal Credentials and Blind Security Logs
China-nexus espionage group Fire Ant compromised Cisco IOS XR routers and TACACS servers to harvest credentials, capture traffic and suppress logs.
Sygnia investigated an intrusion in which Fire Ant expanded beyond VMware hypervisors to Cisco IOS XR routers, TACACS servers and Linux management hosts. The actor deployed purpose-built router implants that hid a GRE tunnel, filtered log messages, captured PCAPs uploaded to external FTP servers, and used TacTap to inject a library into tac_plus and steal TACACS credentials obfuscated with a single-byte XOR key of 0xEF. A Linux backdoor named BridgeAgent masqueraded as a Zabbix agent, persisted via a root systemd unit, disguised itself as /usr/bin/gnome-shell and received commands over TLS on port 443. The group also used Medusa and REPTILE rootkits, SSH backdoors and renamed binaries impersonating SentinelOne and Cybereason agents, while suppressing logs, disabling SELinux and rewriting login history. Sygnia assesses strong overlap with UNC3886 and published IoCs.
78
Campaign Evolution: pseudo
Unit 42 traces the pseudo-Darkleech campaign's 2016 shift from Angler to Neutrino to Rig exploit kits and rotating ransomware payloads.
Unit 42 documents how the pseudo-Darkleech exploit kit campaign evolved through 2016, switching from Angler EK to Neutrino EK in June and to Rig EK in September after Neutrino ceased operations. Payloads rotated from TeslaCrypt to CryptXXX, CrypMIC, and finally Cerber ransomware by October 2016. Injected script on compromised websites changed from 12,000-18,000 character obfuscated blocks to short, unobfuscated hidden iframes starting July 1, 2016.
22
Campaign Evolution: EITest from October through December 2016
Unit 42 details the EITest campaign's late-2016 changes: gates and obfuscation dropped, with Rig EK variants delivering ransomware and infostealers.
Unit 42 tracks the EITest campaign through late 2016, noting it abandoned the gate between compromised websites and exploit kit landing pages after its October 2016 report, and stopped obfuscating injected script URLs by October 15. The campaign primarily uses the Rig-E (Empire Pack) variant and sometimes Rig-V of Rig EK to deliver Cerber and CryptoMix ransomware plus infostealers such as Gootkit, the Chthonic banking Trojan, Ursnif variants, and Latentbot. Tracked since 2014 by Malwarebytes Labs and others, EITest targets unpatched Windows systems without specific victimology.
24
"Blank Slate" Campaign Takes Advantage of Hosting Providers to Spread Ransomware
Unit 42 profiles the Blank Slate malspam campaign: blank emails with double-zipped attachments delivering Cerber ransomware while cycling abused hosting provider domains.
The Blank Slate campaign sends empty emails containing double-zipped archives with macro-enabled Word documents or JavaScript files that launch PowerShell to download ransomware, primarily Cerber, and occasionally Sage 2.0 or Locky. Unit 42 observed 555 campaign domains over seven months, with actors repeatedly registering new domains and cycling abuse of legitimate hosting providers after takedowns. In a five-day January-February 2017 window, at least eight domains across seven IP addresses were observed hosting Cerber payloads.
26
EITest Campaign Evolution: From Angler EK to Neutrino and Rig
Unit 42 details the EITest campaign's shift from Angler to Neutrino and Rig exploit kits while distributing ransomware, downloaders, and banking trojans.
Unit 42 updated its tracking of the EITest campaign, first identified in October 2014, which compromises websites with injected scripts that redirect victims through a gate to exploit kits. After Angler EK disappeared in June 2016, EITest switched to Neutrino and then primarily used Rig EK by August 2016. In September 2016 the campaign began using hex-obfuscated JavaScript and simplified gate URLs, while continuing to distribute payloads including Gootkit, Cerber, Bart, CryptFile2, Vawtrak, Ursnif, and Tinba. Gate infrastructure consistently reused IP blocks such as 85.93.0.0/24 even as domain names changed.
36
60
60
60
60
60
60
60
60