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Dogged Russia-based botnet dismantled after 23-year run

Law enforcement, CrowdStrike and Shadowserver dismantled the 23-year-old Sality P2P botnet that infected more than 11 million devices.

Sality, a Russia-based peer-to-peer botnet active for 23 years and infecting over 11 million devices, was dismantled by law enforcement working with CrowdStrike and the Shadowserver Foundation. CrowdStrike poisoned the botnet's peer list so infected machines permanently disappeared from the operator's view, while domains were seized in a coordinated effort involving the FBI, Justice Department, Europol and authorities from Bulgaria, Hungary and Romania. The financially motivated operation enabled cryptocurrency theft, DDoS attacks and other cyberattacks, and Europol said the effort dates back to 2017; the operators were not named.

CyberScoop · 13d agoMalware

Global sinkhole operation ends Sality botnet’s 23-year run

Law enforcement, CrowdStrike, and Shadowserver sinkholed the 23-year-old Sality P2P botnet, cutting 15,000+ infected machines from its operator.

Sality, active since 2003 as a file-infecting virus with two P2P networks (versions 3 and 4), distributed credential thieves, spam, proxies, and DDoS payloads, and most recently delivered the EggJagger clipboard hijacker that swapped cryptocurrency wallet addresses for at least $150,000 in operator profit. A coordinated sinkhole operation replaced the botnet's super-peer list with defender-controlled sinkholes, and investigators in the US, Bulgaria, Hungary, and Romania seized payload domains. The Shadowserver Foundation is coordinating ISP and CERT notifications to infected device owners.

Help Net Security · 14d agoMalware1

Cops, CrowdStrike disrupt Sality botnet by poisoning the network and diverting into sinkholes

Law enforcement and CrowdStrike disrupted the 23-year-old Sality P2P botnet, isolating 15,000+ infected machines and seizing linked domains.

International law enforcement, working with CrowdStrike and the Shadowserver Foundation, executed a peer-to-peer sinkhole operation against Sality, a botnet active since 2003 that delivered malware to more than 15,000 machines worldwide. Sality's primary payload for eight years was EggJagger, a clipboard hijacker that swaps copied bitcoin and ethereum wallet addresses with attacker-controlled ones, yielding at least $150,000 in stolen cryptocurrency. The US Justice Department, FBI, and DoD Office of Inspector General's Defense Criminal Investigative Service seized Sality-linked domains, with parallel action in Bulgaria, Hungary, and Romania. The Shadowserver Foundation is coordinating with ISPs and CSIRTs to identify infections and notify victims.

The Register · Security · 14d agoMalware in the wild

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

Hackers breach F5 BIG-IP APM devices to deploy Linux rootkit

Sophos analyzed a Linux rootkit on F5 BIG-IP APM devices that injects a fileless PHP web shell, likely after CVE-2025-53521 exploitation.

Sophos analyzed a Linux rootkit targeting F5 BIG-IP APM environments, also tracked by ESET as PoisonedRefresh, which hijacks Apache's apr_dso_load module loader to inject a fileless PHP web shell into memory. The implant intercepts __libc_start_main, hides strings with RC4, creates a password-protected local UNIX socket backdoor for interactive Bash access, and persists across BIG-IP upgrade images while modifying SELinux configuration. It is likely a second-stage payload following exploitation of CVE-2025-53521, a critical RCE flaw F5 reclassified from a DoS issue in March. The ShadowServer Foundation tracked 795 F5 BIG-IP APM endpoints exposed online.

BleepingComputer · 7d agoMalware in the wildCVE-2025-53521