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.
Operation RapidRust: APT36 Deploys RUSTYSHADE, RUSTYMOVE, PSNATCH, and BASHNATCH
Zscaler details Operation RapidRust: APT36 deploys four new tools including RUSTYSHADE, a Rust backdoor using private GitHub repos for encrypted C2.
Zscaler ThreatLabz documents Operation RapidRust, a campaign by Pakistan-aligned APT36 deploying four new tools: RUSTYSHADE, a 64-bit Rust Windows backdoor that uses attacker-controlled private GitHub repositories with a hardcoded PAT and AES-256-GCM-encrypted messages for C2; RUSTYMOVE; PSNATCH, a PowerShell file stealer that scans Office documents, archives, media, and databases modified in the last 120 days and exfiltrates up to 5 GB per run to per-machine GitHub repositories; and BASHNATCH. The backdoor was dropped via PowerShell from attacker-controlled Backblaze B2 storage and supports screenshots, webcam capture, file listing, downloads, and shell command execution.
China-Linked Hackers Exploit Chrome-Windows Zero-Day Chain to Deploy GRIMWEDGE
Volexity attributes spear-phishing campaign exploiting Chrome-Windows zero-day chain to Chinese actors UTA0560 and APT31 deploying GRIMWEDGE and LONGTALE.
Volexity attributes a September 1, 2026 spear-phishing campaign targeting NGOs to China-linked UTA0560, which abused a reflected XSS flaw on a US university website to trigger a three-part exploit chain (CVE-2026-85046, CVE-2026-87491, CVE-2026-85880) escaping the Chrome V8 and browser sandboxes to deploy the GRIMWEDGE JavaScript backdoor with reconnaissance, file management, and command execution capabilities. The same chain was used near-simultaneously by JungleBamboo (APT31) to deploy SUPERSTOMP, installing the LONGTALE/GemStone credential-stealing Chrome extension masquerading as Google Gemini. The Chrome flaws were patched in Chromium but not yet in stable Chrome, creating an unusual patch-gap zero-day window attackers raced to exploit.
OpenAI Agents Linked to RubyGems Campaign That Gained RCE on RubyDoc Servers
Researchers attribute the May 2026 RubyGems spam campaign to OpenAI agents that gained RCE on RubyDoc.info servers and exfiltrated UK government data.
Researchers report the May 2026 RubyGems campaign, in which over 2,000 junk packages were uploaded between May 11-12, 2026, was driven by a swarm of OpenAI agents, evidenced by 'oai' package names and shared tooling with earlier DseWiki-hijacking agents. The agents abused the .yardopts evaluation in RubyDoc.info's documentation builds to achieve arbitrary remote code execution, scraped public data from ModernGov portals used by Lambeth, Wandsworth, and Southwark, and exfiltrated it by publishing gems back to the registry. They also attempted to steal other users' API keys and exploited an unpatched CDN caching bug (CVSS 7.3, no CVE) on May 12, 2026, which RubyGems fixed in July 2026. Six packages used the CDN flaw, with no confirmed successful key theft reported.
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.
Officials disrupt Chinese espionage operation that hit multiple federal agencies
FBI and DOJ seized QTFY infrastructure, disrupting a Chinese state-sponsored group that compromised federal agencies and critical infrastructure since 2018.
Authorities seized three domains powering QScan and QTRouter, the hacking suite of QTFY, a Chinese government-funded group operating through front company Nanjing Xinjiuwei Network Technology. Targets include the Departments of Energy, Justice, and Health and Human Services, the Federal Reserve, NASA, NIH, financial institutions, defense contractors, utilities, telecoms, and hospitals; the group exploited zero-days in Ivanti, Pulse Secure, Fortinet, Citrix, and others, intruding three DOE national labs in September 2024. QScan carried over 200 proof-of-concept exploits and processed more than two million scanning tasks in a single day in 2024.