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Bisonal Malware Used in Attacks Against Russia and South Korea

Unit 42 details a Bisonal malware variant, active since 2014, targeting Russian and South Korean defense organizations via PDF-disguised spearphishing emails.

In early May, Unit 42 discovered a campaign delivering a Bisonal malware variant against at least one Russian communications security and cryptography company and one unidentified organization in South Korea. The variant, in the wild since at least 2014, introduces a new C2 cipher and rewritten networking and persistence code, with only 14 samples collected to date. Attackers spoofed Russian state corporation Rostec in spearphishing emails carrying an executable disguised with a PDF icon; the dropper decrypts an RC4-encrypted DLL and establishes persistence via a registry Run key. Bisonal has been used since 2013 against government, military, and defense targets in South Korea, Russia, Japan, and India, alongside successors Bioazih and Dexbia.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wild

When scanners miss the attack: how Cloudflare Client-Side Security protects storefronts

Cloudflare's Page Shield ML uncovered four malicious JavaScript campaigns on storefronts, including affiliate fraud and a remote-backdoor script, that VirusTotal and URLScan missed.

Cloudflare's Page Shield ML detected four client-side JavaScript operations (eight payloads) in live traffic on online storefronts, enabling affiliate commission hijacking, clickless affiliate theft via hidden iframes, user tracking with a remote-code backdoor, and cloaking of paid mobile visitors. Seven of the eight payloads were absent from VirusTotal and URLScan returned no malicious verdict for any, including a Lnkr-family payload indexed unclassified for roughly 2.5 years. Detection relies on a graph neural network over JavaScript syntax trees, an LLM second opinion on Workers AI, and a frontier-model ensemble voting across benign, magecart, other malware, and cryptomining labels.

Cloudflare Blog · 8h agoMalware in the wild

Hackers Abuse YouTube Gaming Channels and SEO Poisoning to Deploy RATs and Chrome Hijacker

Unit 42 exposed CL-CRI-1171, a pay-per-install operation using YouTube gaming channels and SEO poisoning to deliver RATs and a Chrome hijacker.

Palo Alto Networks Unit 42 identified over 10,000 OfferLoader samples and 11 YouTube channels pushing trojanized installers via gaming lures and SEO-poisoned searches for tools like WinDirStat and Bluetooth drivers. Trojanized Inno Setup installers spawn three payload branches: Insomnia RAT (dual Node.js/Python backdoor that disables Microsoft Defender), ARKTunnel (undocumented RAT hiding its payload in a bitmap image and tunneling TCP/UDP), and Docro Hijacker (alters Chrome protected preferences to hijack search and affiliate links). The pay-per-install model sells each infection to multiple buyers, reaching gamers as well as corporate and government endpoints.

Cyber Security News · 2d agoMalware in the wild1

Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories

Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.

Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.

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

Anthropic Says Russian Hackers Used Claude AI to Automate Malware Evasion

Anthropic disrupted Midnight Blizzard campaigns where AI agents automatically rebuilt malware to evade detection, targeting 20+ government and defense organizations.

Anthropic's threat intelligence report documents the Russian state-nexus actor Midnight Blizzard using Claude to automatically monitor, modify, and redeploy malware until it evaded security products. The campaign hit more than 20 organizations, including Ukrainian and European government ministries, defense bodies, embassies, and think tanks, with mailbox theft from two drone component manufacturers and compromise of hotel guest Wi-Fi via DNS hijacking. The report also describes financially motivated groups GTG-50020 and GTG-50021 targeting AI credentials, including a prompt-injection attack on an automated evaluation sandbox that yielded production API keys and attempts to reach a pre-release Claude model across roughly 30 AI companies.

SecurityWeekupdated · 10h agofirst · 5d agoThreat actor in the wild 19 sources4

Fake GTA 6 download delivers malware-packed bundle to impatient gamers

Huntress found malware disguised as a leaked GTA 6 download bundling NJRAT, DCRAT, an infostealer, and Chaos ransomware used as a wiper.

Huntress analyzed a fake Grand Theft Auto VI ISO whose gta6installer.exe displays a fake 'License not found' error while silently installing payloads. The bundle includes NJRAT and DCRAT remote access trojans, the Mercurial Grabber infostealer, and a Chaos ransomware variant used destructively as a wiper, plus a Yandex Browser drop. The Chaos variant encrypts files up to 200MB, overwrites larger ones, deletes shadow copies, and disables recovery, with no ransom actually demanded. Most components are old malware dating to 2023 and are detected by up-to-date Windows Defender.

Help Net Securityupdated · 6d agofirst · 6d agoMalware in the wild 3 sources1

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

Patch Tuesday - September 2026

Microsoft's September 2026 Patch Tuesday fixes 999 CVEs, a record, with two zero-day privilege escalation flaws already exploited in the wild.

Microsoft published 974 own-product vulnerabilities plus 25 non-Microsoft CVEs, totaling 999 — the most CVEs Microsoft has ever released in a single day. Two flaws are exploited in the wild: CVE-2026-85880, an out-of-bounds write in Windows ALPC granting SYSTEM privileges, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack also leading to SYSTEM. Chrome's V8 zero-day CVE-2026-85046 was patched in Edge on September 2, but Microsoft had not published a corresponding advisory, leaving uncertainty about other Chromium fixes in Edge. October 14 lifecycle changes end servicing for Windows 11 24H2 Home/Pro, Office 2021, and Exchange Server 2016/2019.

Rapid7 Blog · 8d agoVulnerability in the wildCVE-2026-85880CVE-2026-81963CVE-2026-85046+10 CVEs

China-Based Artificial Intelligence Companies Conducting Industrial-Scale Distillation Campaigns Against U.S. AI Companies

NSA, CISA, and FBI warn DeepSeek, Alibaba, and other Chinese AI firms ran industrial-scale distillation of U.S. frontier models, threatening U.S. AI leadership.

A joint NSA, CISA, and FBI Cybersecurity Advisory (AA26-251A) says China-based firms DeepSeek, Moonshot AI, Alibaba, MiniMax, StepFun, and Z.AI extracted billions of tokens from U.S. frontier models including Claude, GPT, Gemini, and Grok, likely with Chinese government knowledge. Campaigns running since at least late 2024 used native APIs, cloud providers, third-party aggregators, gray-market proxy "transfer stations", and shared premium subscriptions to bypass geographic restrictions, evade safeguards, and violate providers' terms of use. The agencies recommend detecting anomalous prompts, accounts, and usage patterns; subtly altering responses to suspected distillers; and cross-organization intelligence sharing. They also call DeepSeek's publicly cited $5.6M training cost misleading because it excludes data acquired through distillation.

CISA Advisories · 8d agoAdvisory in the wild1

New Ted Backdoor Hides Inside Victims' Own HAProxy Builds to Intercept Web Traffic

Rapid7 found a new backdoor, ted, compiled into trojanized HAProxy at two South Korean organizations, with medium-confidence attribution to North Korean actors.

Rapid7 documented a previously undocumented Linux toolkit named ted compiled into the HAProxy load balancer binaries of two South Korean organizations in the automotive and media sectors. The implant intercepts web traffic, serves altered pages only to filtered visitors, and hides C2 exchanges from backend logs and HAProxy statistics; a companion RAT, curlRAT, beacons on a default 12-hour schedule. The toolkit also trojanizes crond, sshd, agetty, atd, and polkitd binaries and sanitizes logs and bash history. Rapid7 attributes the activity with medium confidence to North Korean state-sponsored actors, with domain infrastructure overlapping APT37 listings in maltrail and delivery resembling the Operation SyncHole campaign.

The Hacker News · 12d agoThreat actor in the wild

ASCII smuggling crosses over from AI prompt injection to phishing evasion

Microsoft details high-volume phishing campaign using ASCII smuggling (Unicode tag chars) for filter evasion, peaking at 2.3M messages.

Microsoft researchers observed a high-volume finance-themed phishing campaign using invisible Unicode tag characters (U+E0000–U+E007F), a technique known from AI prompt injection research as ASCII smuggling, to split lure words like 'funding' and evade email filters. Telemetry from Microsoft Defender for Office 365 showed signature hits jump from roughly 21,000 messages on February 8, 2026 to more than 1.3 million on February 9, peaking above 2.3 million on February 11, with elevated weekday activity lasting approximately three months. The discovery emerged from prompt injection protection research, showing AI-era evasion techniques crossing into traditional phishing. Most messages were flagged by layered Defender protections rather than a single Unicode-specific signal.

Microsoft Security Blog · 13d agoPhishing & fraud in the wild1

BraZetsu Malware Turns Compromised Windows Hosts Into Criminal Marketplace Inventory

Group-IB details BraZetsu, a modular Python Windows malware that monetizes compromised-host access through the Infected Marketplace for initial access brokers.

Group-IB attributes BraZetsu to the Exilware threat actor, believed to be native Portuguese speakers targeting Iberian and Latin American e-commerce, financial, industrial, and law enforcement victims. The framework, first observed in early May 2026, uses generative AI for data triage and target prioritization, steals browser histories and digital certificates, and hunts Brazilian CNAB financial remittance files. Access to compromised hosts is sold on the Infected Marketplace from roughly $5.80, letting buyers remotely deploy secondary payloads over WebSocket-linked infrastructure. Some samples evaded detection on VirusTotal; delivery likely uses VBS loaders from a domain also used to distribute the Ousaban banking trojan.

The Hacker News · 13d agoMalware in the wild

China-Linked Fire Ant Hijacks Cisco Routers to Steal Credentials and Blind Security Logs

China-nexus espionage group Fire Ant compromised Cisco IOS XR routers and TACACS servers to harvest credentials, capture traffic and suppress logs.

Sygnia investigated an intrusion in which Fire Ant expanded beyond VMware hypervisors to Cisco IOS XR routers, TACACS servers and Linux management hosts. The actor deployed purpose-built router implants that hid a GRE tunnel, filtered log messages, captured PCAPs uploaded to external FTP servers, and used TacTap to inject a library into tac_plus and steal TACACS credentials obfuscated with a single-byte XOR key of 0xEF. A Linux backdoor named BridgeAgent masqueraded as a Zabbix agent, persisted via a root systemd unit, disguised itself as /usr/bin/gnome-shell and received commands over TLS on port 443. The group also used Medusa and REPTILE rootkits, SSH backdoors and renamed binaries impersonating SentinelOne and Cybereason agents, while suppressing logs, disabling SELinux and rewriting login history. Sygnia assesses strong overlap with UNC3886 and published IoCs.

The Hacker News · 16d agoThreat actor in the wild1

⚡ Weekly Recap: AI-Powered PLC Attacks, GitLab Attacks, Stripe Key Leaks and More

US agencies warn of AI-assisted attacks on exposed Siemens PLCs; the week also saw GitLab CVE-2026-19478 exploited and trojanized npm packages found.

The weekly recap leads with a US government warning that threat actors use AI-generated scripts and Censys/ZoomEye scanning to attack internet-exposed Siemens S7 PLCs in water, energy and manufacturing, calling it an active threat. Other stories include active exploitation of GitLab CVE-2026-19478 (CVSS 9.4, unauthenticated project rewriting), 14 trojanized npm packages delivering the RedC2 4.0 Linux backdoor, and the Zombie Card attack that revives expired Visa cards for contactless payment fraud. It also covers suspected Russian clusters UNC6293, UNC7005 and UNC5976 phishing campaigns, a faster Cloudflare Workers Spectre JWT leak, and a bespoke Cl0p JSP web shell deployed after exploiting PTC Windchill flaws.

The Hacker News · 19d agoThreat actor in the wildCVE-2026-194781

GitLab CVE-2026-19478 Comes Under Active Exploitation Within Days of Disclosure

Unauthenticated attackers are actively exploiting GitLab CVE-2026-19478 (CVSS 9.4) to modify or delete public projects days after disclosure.

GitLab CVE-2026-19478, a CVSS 9.4 code injection flaw exploitable via a GraphQL directive without authentication, allows attackers to modify or delete publicly accessible projects, rewrite repository data, forge merge records, and ban maintainers. Affected versions include GitLab CE/EE 18.2 before 18.11.11, 19.0 before 19.0.8, 19.1 before 19.1.6, and 19.2 before 19.2.4. watchTowr reproduced the flaw within minutes of disclosure and observed in-the-wild exploitation against its honeypot network. Fixes shipped in 19.2.4, 19.1.6, 19.0.8, and 18.11.11; interim mitigations include restricting unauthenticated access to /api/graphql or removing public repository access.

The Hacker News · 26d agoExploit / PoC in the wildCVE-2026-194781

Inside Operation CameraSwarm: How One Actor Took Over 14,000 Dahua Cameras

One actor compromised over 14,000 Dahua cameras in Ukraine and Russia using brute-force, authentication bypass, and cloud relay serial-number abuse.

Hunt.io reconstructed Operation CameraSwarm from an exposed operator directory, revealing one actor compromised 14,000+ Dahua cameras between June 17 and July 22, 2026, mainly in Ukraine and Russia. The toolkit included a brute-force engine, a two-flaw 2021 authentication-bypass chain planting a persistent backdoor account on 1,923 cameras, and abuse of Dahua's cloud relay where 89.4% of probed serials returned open, unauthenticated channels. A SalatStealer Windows binary and Defender-disabling PowerShell script were staged on the same server but appear unrelated to the camera campaign.

Security Affairs · 28d agoThreat actor in the wildCVE-2024-39943CVE-2025-31702