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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 · 1d agoMalware in the wild 2 sources

Sality, one of the longest

US and European authorities, with CrowdStrike and Shadowserver, disrupted the 20-year-old Sality peer-to-peer botnet, severing 15,000+ infected machines from operators.

US and European authorities disrupted the Sality botnet, active since at least 2003, in an operation involving the DOJ, CrowdStrike, the Shadowserver Foundation and agencies in Bulgaria, Hungary and Romania. Researchers reverse-engineered the botnet's peer-to-peer architecture and injected false data into infected machines' 'super peer' lists, cutting more than 15,000 systems off from their operators. For the past eight years Sality primarily distributed EggJagger, malware that replaces clipboard cryptocurrency addresses and is estimated to have netted the operator at least $150,000. No arrests were announced, and CrowdStrike assesses the operator works from Russia's Bashkortostan region.

The Record · 14d agoMalware in the wild

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

Casbaneiro Banking Trojan Uses Distributed C2 Servers to Evade Detection and Target Bank Users

Casbaneiro banking Trojan targets Latin American bank users via phishing PDFs, geofencing, AutoIt staging, and distributed C2 servers to evade detection.

FortiGuard Labs detailed a Casbaneiro banking Trojan campaign observed in August 2026 targeting users in Argentina, Peru, Colombia, and Mexico via fake invoice and legal-notice emails. The operation uses geofenced landing pages, an HTA downloader with WMI-based sandbox checks, a legitimate AutoIt interpreter, and process injection into RegSvcs.exe (fallback mobsync.exe). C2 activation is conditional on victims visiting banking websites, enabling keyboard control, clipboard manipulation, and fake overlay windows for bank-focused fraud, while distributed exfiltration servers and unusual HTTP 403-based signaling hinder analyst correlation.

GBHackers · 3d agoMalware in the wild1

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 · 8d agoMalware in the wildCVE-2025-53521

Iranian Hackers Use Telegram-Controlled Malware to Spy on Dissidents and Journalists

FBI, NCSC, and AIVD detail Iran MOIS spyware CHOSEN BRICK/HEAVYGRAM, Telegram-controlled Windows malware spying on dissidents since 2023.

A September 15 joint advisory from the FBI, UK NCSC, and Dutch AIVD attributes the Windows spyware HEAVYGRAM (NCSC name CHOSEN BRICK) to Iran's Ministry of Intelligence and Security, with the campaign dating to autumn 2023 and targeting dissidents, journalists, and activists in the UK, US, Netherlands, and worldwide. Delivered via messages impersonating known contacts or tech support, the malware assigns each victim a dedicated Telegram bot for command-and-control and exfiltration, and can take screenshots, record microphone audio, steal Telegram/WhatsApp data, saved passwords, and emails, download more malware, and wipe the computer. Persistence uses a registry Run key (SMQDService or winappx) plus Microsoft Defender exclusions, with stolen data exiting via Telegram and cloud storage services like Vultr and Storj. The US Justice Department seized four pro-Iranian leak sites in March that had published stolen victim data.

The Hacker News · 1d agoMalware in the wild1

Chinese-Speaking Hackers Use Noodle RAT Backdoor to Spy on Windows and Linux Systems

Chinese-speaking actors use cross-platform Noodle RAT backdoor to maintain covert access to Windows and Linux systems across Asia-Pacific.

Noodle RAT (also ANGYREBEL/Nood RAT) has been active since at least mid-2016 and was long misidentified as Gh0st RAT or Rekoobe variants until Trend Micro and Cyberint classified it as a distinct multi-platform family. The Windows build (Win.NOODLERAT) is an in-memory modular shellcode backdoor delivered via MULTIDROP and MICROLOAD loaders, while the Linux build supports reverse shells, SOCKS tunneling, and cron persistence after web shell or public-facing service exploitation. It has appeared in intrusions in Thailand, India, Japan, Malaysia, and Taiwan and is linked to Iron Tiger, Calypso APT, Rocke, and Cloud Snooper campaigns spanning espionage and cybercrime. Recently discovered Linux builders 1.0.1 and 1.0.2 indicate the toolkit remains actively maintained.

GBHackersupdated · 17h agofirst · 19h agoMalware in the wild 2 sources1

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

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

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

Twitch extension with 30K installs exposes users’ OAuth tokens

Twitch extension with 30,000+ installs exfiltrates users' OAuth session tokens to Russian-run JeetBot proxy servers.

Socket analysis shows the "Twitch Enhanced Viewer | JeetBot" browser extension, with over 30,000 installs on the official Chrome and Firefox stores, captures the Twitch web client's authorization header and extracts the user's OAuth token. The token is appended as an auth= URL parameter to video playlist requests routed through JeetBot proxy servers, landing in cleartext request logs retrievable by the Russian-language bot service vendor; ten hardcoded Russian-language channels are exempted. Earlier versions used more explicit token exfiltration, and the extension remained live in both stores at publication. Socket recommends removing the extension, disconnecting all Twitch sessions, and re-authenticating.

BleepingComputer · 2d agoMalware in the wild

Four REVSTEALER-Linked Modules Disable Windows Update and Defender to Run a Crypto Miner

Elastic documents four persistent REVSTEALER-linked tools (ProManager, WinUpdate, SoftManager, LockAppHost); LockAppHost disables Windows Update and Defender to run a crypto miner.

Elastic Security Labs identified four previously unreported executables tied to REVSTEALER, a commercial Windows infostealer sold since at least February 2026: ProManager, WinUpdate, SoftManager, and LockAppHost. LockAppHost abuses CMSTP for elevation, adds Microsoft Defender exclusions, disables five Windows Update services and 13 scheduled tasks, then hides a miner in legitimate Windows processes; other modules steal wallets, clipboard-swap crypto addresses, and turn victims into reverse proxies. The components share REVSTEALER tradecraft including packer, runtime function resolution, and Polygon smart-contract backup configuration (EtherHiding). Elastic's detection rule matched about 4,700 VirusTotal samples over the past year; distribution uses hijacked YouTube channels promoting game cheats and a fake 'Claude Opus 5 Free Desktop' app.

The Hacker News · 10d agoMalware in the wild

Hackers Hijack HBO Max Reddit Account to Push 108 ClickFix Malware Ads

Hijacked verified HBO Max Reddit account ran 108 ClickFix malvertising ads delivering AMOS infostealers, Windows loaders, and crypto clipboard hijackers.

HudsonRock and ADAMnetworks identified a cross-platform ClickFix operation dubbed PasteSwitch that abused the compromised verified Reddit account u/hbomax to publish 108 malicious ads over 48 hours, using domains like hbomaxx[.]us and codex-craft[.]com. macOS victims run curl/zsh commands delivering AMOS-related stealers and fake wallets, while Windows users get an InstallFix route using mshta and PowerShell that loads Amatera in memory and disables AMSI. The operation's AnimateClipper and ZigClipper families hijack clipboards to swap cryptocurrency addresses, with C2 domains rotated via Binance Smart Chain contracts. Reddit paused the ads and is investigating.

Cyber Security Newsupdated · 1d agofirst · 2d agoMalware in the wild 7 sources

New KATARU IoT Malware Packs Linux Privilege Escalation Exploits and Mirai-Style DDoS Attacks

Nozomi Networks identified KATARU, a new Mirai-style IoT botnet delivered via Telnet brute force that uses Linux privilege-escalation exploits and encrypted C2 for DDoS floods.

Nozomi Networks identified KATARU in August after a Telnet password-guessing attack against a honeypot retrieved an ARM payload. The malware attempts exploits for CVE-2026-46300 (Fragnesia), CVE-2026-43284 (DirtyFrag), and CVE-2026-31431 (Copy Fail), plus a cgroup v1 release_agent escape, and persists via systemd services, cron tasks, rc scripts, OpenWrt hooks, and Android boot locations. Its C2 uses X25519 key exchange with ChaCha20-Poly1305 encryption and supports TCP, UDP, ICMP, HTTP, QUIC, and DNS floods, plus SSH brute forcing and command execution; embedded exploit shellcode in the ARM build targeted x86, suggesting untested copied code.

Cyber Security News · 5d agoMalware in the wild 2 sourcesCVE-2026-46300CVE-2026-43284CVE-2026-31431

Hackers Deploy New SloppyRAT via ClickFix to Enable Ransomware Lateral Movement

Zscaler discovered SloppyRAT, a ClickFix-delivered RAT that gives ransomware operators reconnaissance, remote execution, and SOCKS proxy pivoting for lateral movement.

Zscaler identified SloppyRAT in June 2026, linked to a ransomware-related threat actor. The infection chain starts with a ClickFix lure abusing finger.exe over TCP port 79, then uses curl.exe, IronPython, CastleLoader, and CastleRAT before reflectively loading SloppyRAT as a DLL in memory. The RAT supports HTTPS command-and-control, system inventory, file operations, Defender tampering, and a reverse SOCKS proxy, with evasion features including runtime code encryption, indirect syscalls, certificate pinning, and a possible EtherHiding blockchain fallback. Its persistence code is buggy and the malware appears under development, but the pre-encryption foothold gives defenders a window to stop intrusions.

Cyber Security News · 5d agoMalware in the wild 3 sources

ThreatsDay: 296K IoT Botnet, 100+ Water Systems Targeted, SharePoint RCE Chain + 27 New Stories

Weekly ThreatsDay bulletin details a ShinyHunters-style social engineering hit on ReliaQuest, the 296,000-device Dysphoria IoT botnet, and several new malware families.

ReliaQuest confirmed a social engineering attack on August 22, 2026, in which an attacker used a fake SSO page and MFA push approval to gain brief view-only access to an identity dashboard, with tactics matching ShinyHunters, which has since listed the firm on its leak portal. The Shadowserver Foundation reported the Dysphoria botnet has compromised nearly 296,000 IoT devices for DDoS attacks and recently added residential proxy capability. Cisco Talos documented JWR, an operator-driven phishing-as-a-service framework linked to The Outsider that harvests credentials, identity documents, and 2FA codes over an encrypted WebSocket. New malware coverage includes the Octagon Android fraud bot ($1,400/month), the C2Looper Rust backdoor delivered via ClickFix, and the Aeternum loader that moved C2 to the Polygon blockchain.

The Hacker News · 15d agoMalware in the wild

Fake Software Installers Disable Windows Update and Weaken Microsoft Defender

Fake software-download sites distribute installers that disable Windows Update and weaken Defender, attributed to China-linked cluster Silver Fox.

Microsoft says an active campaign uses counterfeit vendor websites on .com.cn and .hl.cn infrastructure with Chinese-language lures to deliver server-side generated installers that establish scheduled-task persistence, add Defender exclusions, delete shadow copies, and stop services including wuauserv, UsoSvc, uhssvc and WaaSMedicSvc. Victims span healthcare, manufacturing, gaming, technology, logistics, government and education, primarily China-based operations of multinationals and Chinese-speaking users. Microsoft assesses with moderate confidence the activity matches the Silver Fox (Yinhu) cluster, historically tied to Gh0st RAT and ValleyRAT, with C2 over non-standard ports like 5090 and 7088-7090 via domains iualef[.]net and oijfwe[.]net. Kaspersky separately detailed a QN Wallpaper DLL-sideloading chain delivering ValleyRAT.

The Hacker News · 14d agoMalware in the wild1

Hackers Abuse AutoIt to Inject AsyncRAT Into Microsoft-Signed Windows Process

Attackers use AutoIt and an invoice-themed batch file to inject AsyncRAT into Microsoft-signed charmap.exe for stealthy remote access.

Point Wild Threat Intelligence documented a five-stage campaign starting with 'Right-click to open Invoice Details.bat' that launches hidden PowerShell, drops a renamed AutoIt interpreter and encrypted loader into a random Temp folder, and persists via a Startup-folder batch file. The loader decrypts AsyncRAT only in memory and injects it into the Microsoft-signed charmap.exe (Windows Character Map) process, leaving no payload file on disk. The final payload patches AMSI inside the infected process and includes screen-capture code that prepares images for transfer to a command-and-control server at 158[.]51[.]122[.]136:4944.

Cyber Security News · 3d agoMalware in the wild1

BambooToken malware controls Windows and Linux systems via MQTT

Lumen Black Lotus Labs exposes BambooToken, a China-aligned malware framework using MQTT C2 to backdoor Windows and Linux systems at roughly a dozen enterprises.

Lumen's Black Lotus Labs documented BambooToken, a previously unknown malware framework active since at least 2023 that adopted MQTT for command-and-control in 2024-2025 variants targeting Windows and Linux. Infection occurs via DLL side-loading through digitally signed Tendyron OnKey USB-token software or an impersonated Kingsoft Office installer; dead code suggests keylogging, clipboard theft, audio/webcam capture, and screenshot modules. Telemetry identified roughly a dozen compromised entities, mostly in Asia and South America, including a Hong Kong GitLab server and possibly users of the SpeedCN VPN service. Targeting patterns are consistent with China-aligned operations, though no attribution to a known cluster was made.

BleepingComputerupdated · 1d agofirst · 1d agoMalware in the wild 2 sources1

ValleyRAT Backdoor Hides in Signed Adware That Users Add to Antivirus Exclusions

Silver Fox distributes ValleyRAT via signed QN Wallpaper adware, sideloading a malicious libcef.dll into a trusted process to evade defenses.

Kaspersky reports the Silver Fox threat actor disguising the ValleyRAT backdoor (Winos 4.0) inside a modified, signed copy of the QN Wallpaper adware tool, using DLL sideloading to run within a trusted process. The installer disables Windows Defender via the DisableAntiSpyware registry key, adds autorun entries, and elevates via runas when needed; ValleyRAT steals keystrokes, clipboard data, and screenshots and can mark its process critical to trigger BSOD if killed. Kaspersky recorded more than 100,000 ValleyRAT detections affecting over 1,500 unique users in 2026, mostly in China and India, with prior campaigns against Japan, India, and Russia.

The Hacker News · 16d agoMalware in the wild