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IoT Under Siege: The Anatomy of the Latest Mirai Campaign Leveraging Multiple IoT Exploits

Unit 42 tracks a Mirai botnet campaign exploiting over 20 IoT vulnerabilities in routers, cameras and DVRs to build DDoS botnets since March 2023.

Since March 2023, Unit 42 has tracked threat actors exploiting more than 20 IoT vulnerabilities to spread a Mirai botnet variant, first seen downloading payloads from zvub.us on March 14, 2023. Exploited flaws span CVE-2023-1389 (TP-Link Archer), CVE-2022-30525 (Zyxel), CVE-2022-31499 (Nortek) and many router, camera and DVR bugs. The variant decrypts configuration strings with an XOR key derived from 0xDEADBEEF and lacks built-in credential brute forcing, so spreading relies on manual operator exploitation. Two campaigns observed since October 2022 share infrastructure and near-identical samples.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wildCVE-2019-12725CVE-2019-17621CVE-2019-20500+13 CVEs1

PoisonedRefresh: A Fileless Linux Rootkit That Injects PHP Web Shells Into F5 BIG-IP APM Server Memory

Sophos details PoisonedRefresh, a fileless Linux rootkit that injects a memory-resident PHP web shell into F5 BIG-IP APM after exploitation of CVE-2025-53521.

On September 8, 2026, SophosLabs published an analysis of Linux/Agnt-IC (dubbed PoisonedRefresh by ESET) found in compromised F5 BIG-IP Access Policy Manager environments. Initial access leverages CVE-2025-53521, an unauthenticated RCE in BIG-IP APM when an access policy is configured on a virtual server; F5 confirmed exploitation and links the activity to cluster c05d5254, while Shadowserver observed 795 exposed vulnerable endpoints. A first stage hidden in a modified umount binary modifies /usr/sbin/httpd and SELinux configuration and embeds itself in BIG-IP upgrade images for persistence. The second-stage ELF intercepts __libc_start_main, hooks apr_dso_load, and injects a PHP web shell into libphp memory via mmap manipulation, leaving no disk artifacts, and exposes a /bin/bash shell via a local UNIX domain socket instead of a TCP port.

Security Affairs · 7d agoMalware in the wildCVE-2025-53521

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.

Cyber Security News · 2d agoMalware in the wild

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.

GBHackers · 2d agoMalware in the wild 9 sourcesCVE-2026-20079CVE-2026-20316

Stealth rootkit targeting F5 BIG-IP could expose enterprise identity gateways

Sophos analyzed a stealth Linux rootkit that hides a web shell in memory on compromised F5 BIG-IP APM identity gateways, evading file-based detection.

Sophos analyzed a second-stage Linux rootkit implant found in compromised F5 BIG-IP APM environments running Apache and PHP, linked to exploitation of CVE-2025-53521, an unauthenticated RCE. The implant hooks Apache's PHP-loading process and serves modified in-memory versions of three legitimate webtop PHP files (apm_css.php3, full_wt.php3, webtop_popup_css.php3), leaving on-disk files untouched so hashes and integrity checks pass. It also establishes access via an authenticated local UNIX socket that can provide an interactive /bin/bash session. Experts warn compromised APM appliances, which handle federated SSO and terminate TLS at enterprise perimeters, could enable SSO token theft and lateral movement to trusted downstream applications.

CSO Online · 6d agoMalware in the wildCVE-2025-53521

Hackers deploy Linux rootkit on F5 BIG-IP APM devices, hiding web shell in memory

Sophos analyzed a Linux rootkit, tracked as PoisonedRefresh, on hacked F5 BIG-IP APM devices hiding an in-memory web shell linked to exploited CVE-2025-53521.

Sophos and ESET analyzed an implant (named PoisonedRefresh by ESET) deployed on compromised F5 BIG-IP APM appliances, which serves enterprise, financial, government, and public sector deployments. The second-stage payload intercepts __libc_start_main, hooks Apache's APR module loader (apr_dso_load), RC4-encodes key strings, and rewrites PHP file reads in memory to embed a web shell inside legitimate scripts like apm_css.php3, full_wt.php3, and webtop_popup_css.php3, leaving on-disk files unchanged. A related installer component infects /usr/sbin/httpd, persists across BIG-IP upgrade images, modifies SELinux configuration, and deploys the payload. The malware also creates a Unix domain socket at /run/bigtlog.pipe that hands authenticated local connections to /bin/bash; F5 links the activity to CVE-2025-53521, an unauthenticated RCE in BIG-IP APM already exploited in the wild.

Help Net Security · 7d agoMalware in the wildCVE-2025-535211

Hackers Exploit Critical FortiGate Flaw to Deploy AI-Assisted PivotC2 RAT

SOCRadar says attackers exploit FortiGate CVE-2025-25249 to deploy the PivotC2 Node.js RAT, compromising 178 of 30,000 targeted devices and stealing credentials.

SOCRadar's Threat Research Unit reports active exploitation of CVE-2025-25249, a CVSS 9.8 heap-based buffer overflow in the cw_acd daemon of FortiOS and FortiSwitchManager, via crafted CAPWAP requests to UDP port 5246, compromising at least 178 of 30,000 targeted internet-exposed FortiGate devices since July 2026. The campaign deploys PivotC2, a Node.js RAT that provides interactive shells, SOCKS5/HTTP proxying, port forwarding, network scanning, and automated configuration harvesting that decrypts stored FortiGate credentials, including VPN pre-shared keys, SSL-VPN credentials, and LDAP secrets. Russian-language artifacts, AD enumeration, browser credential theft, RDP enablement, and exfiltration of Exchange .pst files to Wasabi S3 point to a Russian-speaking, financially motivated group; two US organizations confirmed full-network intrusions. Fixes include FortiOS 7.6.4/7.4.9/7.2.12/7.0.18+ and FortiSwitchManager 7.2.7/7.0.6+, plus blocking CAPWAP on internet-facing interfaces.

GBHackers · 7d agoMalware in the wildCVE-2025-252492

Home & Small Office Wireless Routers Exploited to Attack Gaming Servers

Unit 42 details an updated Gafgyt botnet variant exploiting Zyxel, Huawei, and Realtek router vulnerabilities to recruit devices for DoS attacks on gaming servers.

Unit 42 researchers identified an updated Gafgyt variant derived from the JenX botnet that combines three remote code execution exploits: CVE-2017-18368 (Zyxel P660HN-T1A), CVE-2017-17215 (Huawei HG532), and CVE-2014-8361 (Realtek RTL81XX chipset). Shodan scans show more than 32,000 wireless routers worldwide potentially vulnerable to these exploits. The exploits act as droppers, pulling architecture-specific binaries from a malicious server (185.172.110.224), and the botnet performs denial-of-service attacks against gaming servers, most notably Valve Source engine servers.

Palo Alto Unit 42 · Aug 18, 2026Malware in the wildCVE-2017-18368CVE-2017-17215CVE-2014-83611

Mirai Variant MooBot Targeting D

Unit 42 observed the MooBot Mirai variant exploiting four D-Link vulnerabilities to compromise unpatched routers for use in DDoS attacks.

Unit 42 captured attacks exploiting four D-Link remote code execution vulnerabilities: CVE-2015-2051, CVE-2018-6530, CVE-2022-26258, and CVE-2022-28958, with three rated critical at CVSS 9.8. The exploits download the MooBot malware, a Mirai botnet variant, from infrastructure at 159.203.15.179 via wget. Compromised devices fall under full attacker control and can be used for distributed denial-of-service attacks. D-Link has published bulletins for all four flaws, but unpatched devices remain exposed.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wildCVE-2015-2051CVE-2018-6530CVE-2022-26258+1 CVEs

Mirai Variant V3G4 Targets IoT Devices

Unit 42 tracked the Mirai variant V3G4 exploiting 13 vulnerabilities across IoT devices and servers from July-December 2022 to build a DDoS botnet.

From July to December 2022, Unit 42 observed three campaigns spreading V3G4, a Mirai botnet variant, by exploiting 13 vulnerabilities, including CVE-2022-26134 in Atlassian Confluence and CVE-2019-15107 in Webmin. The campaigns shared the same C2 domains containing the string 8xl9, nearly identical shell script downloaders, and the same XOR keys, suggesting a single threat actor. The malware brute-forces telnet and SSH credentials, terminates rival botnet processes via a stop list, and receives DDoS commands from its C2. Compromised servers and networking devices are absorbed into the botnet for further attacks.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wildCVE-2012-4869CVE-2014-9727CVE-2017-5173+6 CVEs