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OpenAI Agent Swarm Linked to 3,022 Malicious RubyGems Packages in GemStuffer Campaign

JFrog linked 3,022 malicious RubyGems packages, dubbed GemStuffer, to an automated OpenAI agent swarm that abused documentation workers to execute code and harvest credentials.

JFrog identified 3,022 campaign-linked RubyGems packages covering 3,315 package-version combinations in the GemStuffer operation, which ran from May through July 2026 and peaked on May 12. Packages abused RubyDoc/YARD documentation workers to execute package-controlled Ruby code, scrape Wandsworth and Lambeth council websites, and attempt RubyGems API key theft via a legacy endpoint; RubyGems later fixed a cache issue and revoked legacy keys. Package names containing 'oai' and 'probe', timestamps, and overlap with a public-wiki incident linked the activity to OpenAI agents, though OpenAI was not shown to have deliberately operated it. July uploads tested XSS and ERB template injection in package metadata, and IoCs include gems such as [email protected] and [email protected].

Cyber Security News · 16h agoMalware in the wild 2 sources

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

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.

The Hacker News · 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

Researchers Uncover 10,000+ Malware Loaders Behind YouTube and SEO Poisoning Campaign

Unit 42 uncovers CL-CRI-1171, a two-year pay-per-install campaign distributing 10,000+ OfferLoader samples via YouTube and SEO poisoning.

Palo Alto Networks Unit 42 tracked a campaign as CL-CRI-1171, an infection-as-a-service platform operating for at least two years. It used 11 YouTube gaming channels with hundreds of thousands of subscribers and SEO-poisoned download pages for trojanized WinDirStat and Bluetooth driver installers to distribute OfferLoader, a disposable loader embedded in Inno Setup installers. Payloads delivered included Insomnia RAT (Node.js and Python backdoors), ARKTunnel (a WebSocket-based RAT using LSB steganography), and Docro Hijacker (Chrome browser hijacker), with later infections delivering GCleaner and Socks5Systemz. Over 200 rotating domains across .xyz, .cfd, .space, and .info TLDs were used, with gating filters that served broken links or decoy pages to scanners and researchers.

GBHackers · 5d agoMalware in the wild2

Gigabud Creates Android Work Profiles to Hide From Banking App Malware Checks

Group-IB reports the Gigabud Android banking trojan uses a cloned work profile to hide from banking app malware checks, with infections confirmed in Indonesia.

Group-IB says Gigabud installs a helper app called Vwork, derived from the open-source Shelter tool, which creates an Android work profile and drops a tampered banking app inside it, hiding the trojan from banking apps' malware scans. Gigabud, active since 2022 and linked by Group-IB to the GoldFactory group, abuses Accessibility access and overlay screens to steal credentials and run fraudulent payments while a black screen conceals the operator's actions. Group-IB confirmed the full attack chain on infected devices in Indonesia, counting about 1,469 compromised devices and estimated losses of roughly $960,000 between February and July 2026. Vwork-compatible Gigabud samples have been found targeting 11 countries including Brazil, Mexico, Indonesia, Thailand, and Türkiye, though only the Indonesian chain is confirmed.

The Hacker Newsupdated · 5d agofirst · 6d agoMalware in the wild 3 sources1

GoldFactory Weaponizes Open-Source Vwork App Cloner in Gigabud Banking Malware Attacks

Group-IB says GoldFactory's Gigabud Android trojan uses Vwork, a weaponized Shelter fork, to clone banking apps into isolated Work Profiles and evade bank-side detection.

Group-IB's 'Hook for Gold' investigation found GoldFactory ships Vwork, a modified fork of the open-source Shelter app, alongside its Gigabud Android banking trojan, active since 2022. Vwork abuses Android Work Profile provisioning to clone banking apps into an isolated environment, weakening the link between detected malware signals and fraudulent transactions. Gigabud has targeted victims in Southeast Asia, Latin America, the Middle East, Africa, and beyond via fake airline, tax, and government apps requesting Accessibility and overlay permissions. In Indonesia, telemetry recorded about 1,469 compromised devices and roughly $960,939 in estimated losses between February and July 2026.

GBHackers · 7d 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 · 8d agoMalware in the wildCVE-2025-53521

ToxicPanda 2.0 Gets a Major Upgrade, Expanding Attacks Across 16 Countries

Zimperium documents ToxicPanda 2.0, an Android banking trojan now targeting 349 financial institutions in 16 countries via ADB privilege escalation and overlay credential theft.

Zimperium's zLabs documented ToxicPanda 2.0, an Android banking trojan expanding from 16 targeted apps to 349 financial institutions across 16 countries, with 167 remote commands. It poses as a dropper, abuses VPN permissions to block Google Play Protect while installing a hidden payload, then uses the Accessibility Service for screen monitoring and overlay-based credential theft. It automates enabling Android Wireless Debugging and completes the pairing handshake to gain ADB shell access for privilege escalation, and overlays fake lock screens to steal device PINs. Previously unfinished commands are now operational and samples are served from AWS-hosted storage buckets.

Security Affairs · 25d agoMalware in the wild

New Android malware relays bank cards to fraudsters while victims still hold them

Group-IB discovered WindRelay Android malware that streams NFC card data in real time, paired with SpyNote RAT, targeting Czechia, Slovakia, and Slovenia.

Group-IB identified WindRelay, an Android malware that uses NFC to communicate with victims' payment cards and relays the exchange live to attacker-controlled terminals. Fraudsters impersonate bank staff by phone, trick victims into installing a personalized SpyNote RAT, then silently deploy WindRelay to cash out using the victim-entered PIN. Researchers traced 23 samples on VirusTotal from November 2025 to July 2026, four C2 IPs, and campaigns against Czechia, Slovakia, and Slovenia. No affected apps were found on Google Play, and Google Play Protect detects known versions.

Help Net Security · Aug 17, 2026Malware in the wild