Sandworm-Linked Cyclops Blink Returns With Network Scanning and Packet-Sniffing Capabilities
Sophos uncovers a 64-bit Cyclops Blink variant on hacked Cisco FMC appliances, adding internal network scanning and selective packet capture; linked to Sandworm.
Sophos CTU analyzed a new 64-bit x86-64 Cyclops Blink implant (timezone_check) deployed on Cisco Secure Firewall Management Center appliances compromised via CVE-2026-20079 authentication bypass and CVE-2026-20316 low-privileged login. The activity is assessed with high confidence as Russian-nexus, with a moderate-confidence link to Sandworm (IRON VIKING, also tracked as Seashell Blizzard). The implant runs a parent controller plus five worker modules, masquerades as [kworker/0:1], persists via SysV init scripts at /lib/tz/timezone_check, and beacons to hard-coded C2 89.34.96.56 over a custom TLS protocol on ports 43856 and 49172. New module 0x11 scans internal IPv4 networks for SSH, SMB, LDAP, VMware, HTTP/HTTPS and VPN services, while module 0x12 performs filtered packet capture that can expose cleartext credentials, cookies and tokens.
Cyclops Blink Evolves Into x86-64 Linux Implant With Packet Sniffing and Internal Network Scanning
Sophos uncovers a new x86-64 Cyclops Blink Linux implant with packet sniffing and internal network scanning on compromised Cisco FMC appliances.
Sophos identified a 64-bit Linux Cyclops Blink implant in August on compromised Cisco Firewall Management Center devices, persisting via SysV init scripts and masquerading as the process 'kworker01'. The modular malware runs five child processes for reconnaissance, file transfer, scanning, packet capture, and persistence, and beacons hourly over outbound TLS to hardcoded C2 89.34.96.56 on ports 43856 and 49172. The family was previously tied to Russian-linked Sandworm activity on WatchGuard appliances, though Sophos treats 2026 attribution cautiously. The packet-capture module applies configurable filters to retain credentials, cookies, and authentication tokens from raw Ethernet traffic.
F5 BIG-IP APM Malware Injects a PHP Web Shell Into Memory, Evading Disk Scans
Sophos found F5 BIG-IP APM malware that injects a PHP web shell into Apache's memory, evading disk scans, linked to exploited CVE-2025-53521.
Sophos's September 7 analysis describes malware tied to F5's c05d5254 activity that hooks apr_dso_load, modifies the libphp PHP module in memory, and injects a PHP web shell when Apache loads apm_css.php3, full_wt.php3 or webtop_popup_css.php3, leaving on-disk files clean. A separate installer infects /usr/sbin/httpd and umount, runs before Apache starts, disables SELinux (per ESET's related PoisonedRefresh analysis), and opens a local socket at /run/bigtlog.pipe for shell access. The activity is linked to CVE-2025-53521 in BIG-IP APM, rated 9.8 CVSS 3.1, patched in October 2025, added to CISA KEV on March 27, 2026.
Muhstik Botnet Attacks Tomato Routers to Harvest New IoT Devices
Unit 42 found a Muhstik botnet variant brute-forcing Tomato router web authentication to harvest IoT devices for crypto mining and DDoS attacks.
Palo Alto Networks Unit 42 researchers in December 2019 identified a new Muhstik botnet variant scanning Tomato routers on TCP 8080 and brute-forcing default admin credentials, targeting roughly 4,600 exposed devices found via Shodan. The variant also scans WordPress and Webuzo installations and exploits the Oracle WebLogic deserialization flaw CVE-2019-2725 for unauthenticated remote code execution. Muhstik, active since March 2018, self-propagates like a worm and typically monetizes infections through cryptocurrency mining and DDoS attacks controlled via an IRC C2 channel.