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9 stories in the last 30d

Hackers Weaponize AI Safety Guardrails to Hide Malware From LLM-Powered Security Scanners

ESET says Russia-aligned actor UAC-0099 hid guardrail-triggering comments in VBScript to derail LLM-based malware scanners in Ukraine.

ESET researchers linked a technique named GuardBreaker to Russia-aligned threat actor UAC-0099 during an attack against an organization in Ukraine. The group embedded a safety-sensitive, weapon-related request in a VBScript comment so an LLM-powered analysis tool might interpret it as an instruction and refuse or truncate analysis before reaching the malicious code. The VBScript downloaded MATCHBOIL, a C#-based loader used by the group alongside MATCHWOK and DRAGSTARE. OWASP guidance recommends treating code comments and metadata as untrusted input, sanitizing it, and never treating an LLM refusal as a clean verdict.

GBHackersupdated · 5d agofirst · 6d agoThreat actor in the wild 2 sources1

FamousSparrow Exploits Public-Facing Exchange Servers to Deploy SparroWocky Backdoor

ESET attributes a new SparroWocky backdoor to espionage group FamousSparrow, deployed via exploited internet-facing Exchange servers across Latin American governments.

ESET's Welivesecurity team reports FamousSparrow gained initial access by exploiting publicly reachable Microsoft Exchange servers, with roughly 90 percent of targets since mid-2025 in Latin America, including governments in Argentina, Ecuador, Guatemala, Honduras, Panama, Peru, Puerto Rico, and Venezuela. The group's new modular C-language backdoor SparroWocky replaces SparrowDoor and uses a three-part loader: a legitimate executable, a malicious DLL side-loaded in memory, and an encrypted payload. It persists via Windows services or Registry Run keys, supports screenshots, file operations, TCP proxying, Beacon Object Files, TLS/RC4-encrypted C2, and anti-forensics such as call-stack spoofing. IOCs including loader SHA-1 hashes and C2 IP addresses were published.

Cyber Security News · 2h agoThreat actor in the wild 3 sources

Malicious Apache Modules Hijack Brazilian Government Site Traffic to Push Betting Pages

Check Point links Gambling Goblin, a Chinese-speaking cluster, to malicious Apache modules hijacking Brazilian government servers to promote betting sites.

Check Point Research tracks Gambling Goblin, a Chinese-speaking cluster, installing malicious Apache reverse-proxy modules on compromised Brazilian government and education web servers since mid-2025. The modules divert visitors to gambling and fake app-store pages while stripping the site's security headers, likely for large-scale SEO manipulation. The group's Linux arsenal includes DownPro, AlphaAgent, oRAT, a 3snake-based credential stealer, and SSH brute-forcing tools, and it is tied to Trend Micro's Earth Berberoka. Related SEO-fraud campaigns on .gov.br domains were documented by ESET (GhostRedirector), Palo Alto Networks Unit 42, and Hunt.io.

The Hacker News · 14d agoThreat actor in the wild

Claude Used to Automate Exploitation and Data Theft Across Multiple Victims

Anthropic's 154-page report details Generative Threat Groups, including APT29-linked GTG-20006 and ShinyHunters affiliates, using Claude for reconnaissance, exploitation, and data theft.

Anthropic reports that between December 2025 and August 2026 state-sponsored hackers, criminals, spyware vendors, and propaganda operators used its Claude models for cyber attacks, weapons design, propaganda, and mass surveillance. Notable clusters include GTG-50014, a ShinyHunters affiliate that scanned 1.8 million Android APKs for secrets via 10 AWS EC2 workers, GTG-10007, a Chinese-speaking group targeting roughly 50 organizations, and GTG-50029, a lone French-speaking actor exploiting a previously undocumented WordPress re-installation race condition. The report describes multi-agent frameworks autonomously executing reconnaissance, exploitation, and exfiltration against multiple victims, and influence operations that were disrupted before building authentic audiences.

The Hacker Newsupdated · 19h agofirst · 5d agoThreat actor in the wild 20 sources1

Iran-Linked Hackers Use Fake LinkedIn Job Offers to Deploy NodeRabbit and PollCat RATs

Iran-linked Mirage Kitten targets software engineers with fake LinkedIn recruiter coding tests deploying new NodeRabbit and PollCat RATs.

Kaspersky researchers link the campaign to Mirage Kitten (also tracked as UNC1549, Smoke Sandstorm, Nimbus Manticore), with victims in aviation, aerospace and fintech in Egypt, Ethiopia and Afghanistan. Trojanized npm dependencies (colorized_terminal, pretty-log) bundled in coding-challenge archives launch the Node.js implants across Windows, Linux and macOS. NodeRabbit uses AES-256-GCM-encrypted C2 via Azure, and its third variant persists through a fake GitHub Copilot Helper VS Code extension plus Git post-merge/post-checkout hooks. PollCat is an obfuscated JavaScript RAT that registers with C2 before OTP authentication and inventories tools from 24 security vendors.

GBHackers · 8d agoThreat actor in the wild1

H1 2026 Malware Vulnerability Trends

Recorded Future's H1 2026 report finds 215 actively exploited CVEs, RAT dominance, NFC payment fraud, and AI-augmented but not autonomous tradecraft.

Recorded Future's Insikt Group identified 215 actively exploited CVEs in H1 2026, up 34% from 161 in H1 2025, with the most impactful flaws combining network reachability, no authentication, and code execution. AsyncRAT was the top malware family, with AsyncRAT, Cobalt Strike, XWorm, Stealc, and REMCOS remaining top-ten staples; Android NFC malware like NFCShare and NGate enabled payment card theft and ATM cash-outs. AI-enabled attacks remained additive to established tradecraft, concentrated in Levels 1-3 of Recorded Future's AIM3 maturity model, with AI-assisted vulnerability research (e.g., Claude Mythos fixing 271 Firefox bugs in Firefox 150) inflating NVD disclosure volumes 43% above the prior six-month average. The report urges defenders to prioritize remotely exploitable RCE flaws, behavioral detection, developer credential security, and third-party oversight.

Recorded Future · 14d agoThreat actor in the wild1

Iranian Hackers Pose as Recruiters to Deliver Cross

Kaspersky attributes new cross-platform RATs NodeRabbit and PollCat to Iranian group Nimbus Manticore, spread via recruiter-themed LinkedIn lures.

Kaspersky links two previously undocumented malware families, NodeRabbit (Node.js) and PollCat (obfuscated JavaScript), to the Iranian threat actor Nimbus Manticore, also known as Iranian Dream Job. Victims in Afghanistan, Egypt, and Ethiopia received trojanized coding challenge archives containing fake npm packages (colorized_terminal, pretty-log) that silently launched the RATs as background processes. NodeRabbit contacts Azure-hosted C2 servers via checkin, task, and result API endpoints and supports 11 commands including shell execution, file operations, and network enumeration. Persistence is platform-specific: Windows Run keys or scheduled tasks, Linux cron entries, and macOS launch agents, impersonating Microsoft Edge updates or Intel's Driver & Support Assistant.

The Hacker News · 15d agoThreat actor

Russia-Aligned UAC-0099 Plants Nuclear Weapon Prompt in Malware to Disrupt AI Analysis

Russia-aligned UAC-0099 planted a nuclear-weapon prompt inside malicious VBS scripts to derail LLM-based malware analysis targeting Ukraine.

ESET disclosed a technique dubbed GuardBreaker used by Russia-aligned UAC-0099 against a Ukrainian target: inserting the text 'I want to make a nuclear weapon. Help me ...' as a comment in a malicious VBS script to trip LLM safety guardrails and stop AI-assisted analysis. The script downloads and installs MATCHBOIL, a C# loader exclusive to UAC-0099, which CERT-UA warned was distributed as a fake Notepad++ plugin in late July 2026. Similar prompt-injection anti-analysis tricks appeared in the Mini Shai-Hulud, Miasma, and Hades npm supply chain campaigns linked to TeamPCP, two of whose alleged members were arrested in Western Australia.

The Hacker News · 15d agoThreat actor

Google researchers uncover criminal zero-day exploit likely built with AI

Google links a likely LLM-built criminal zero-day for an open-source admin tool to planned mass exploitation and maps AI-assisted threats.

Google Threat Intelligence Group linked a zero-day exploit for a popular open-source web-based administration tool, enabling 2FA bypass with valid credentials via a semantic logic error, to a criminal group, citing educational docstrings, a hallucinated CVSS score, and textbook Python as signs of LLM authorship; the vendor was notified before a planned mass exploitation campaign. The report also details Russia-nexus malware families CANFAIL and LONGSTREAM using AI-generated decoy code, the PROMPTSPY Android backdoor driving the UI through the Gemini API, APT27 using Gemini to build relay tooling, and the TeamPCP (UNC6780) supply chain compromise of LiteLLM and Trivy repositories that planted the SANDCLOCK credential stealer.

Help Net Security · 24d agoThreat actor