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Iranian Hackers Use Fake MRI Results to Infect Victims With CHOSEN BRICK Spyware

Iranian state-linked hackers deliver CHOSEN BRICK Windows spyware via fake MRI results to surveil dissidents, activists, and journalists in the UK, US, and Netherlands.

A joint advisory from the UK NCSC, FBI, and the Netherlands' AIVD links Iranian state-linked actors to CHOSEN BRICK, a Windows spyware family used for long-term surveillance since at least 2025. Targets are approached on WhatsApp or Telegram with tailored lures such as fake MRI scan results or application files, and operators often redirect victims to personal devices to bypass corporate controls. The malware persists via Run registry keys, adds antivirus exclusions, uses a per-victim Telegram bot for command and control, and exfiltrates data through cloud storage and proxy services. Capabilities include screenshots, audio recording, email and messaging theft, command execution, file deletion, data wiping, and some victims' details have appeared on pro-Iranian leak sites for harassment.

Cyber Security Newsupdated · 3h agofirst · 15h agoThreat actor in the wild 6 sources

ThinkPrior: Zero-Rollout Difficulty Priors for Cold-Start Prompt Selection in RLVR

ThinkPrior builds zero-rollout difficulty priors via an offline verifier-anchored pass, halving silent groups in RLVR and cutting wasted rollouts on Qwen2.5-Math-7B.

In GRPO-based RLVR, groups where all rollouts are correct or all are wrong yield zero advantages and consume about 39% of a run's rollouts under uniform sampling. ThinkPrior initializes a Beta posterior from an external anchor pass's verifier-scored pass rate, selecting prompts by expected learnability before any target-policy rollout, without changing the loss or optimizer. On Qwen2.5-Math-7B across sixteen seeds it more than halves early silent groups and cuts wasted rollouts through step 30 by nearly a fifth, with no detected final-accuracy difference. The ThinkPrior+DAPO composition reduces generated rollouts by 10.6% at an equal 3,840-rollout update budget.

arXiv cs.AI / cs.LG / cs.CL · 8d agoAI research1

[AINews] 10% worse, 100x cheaper, 10000x faster: Why Simulation is taking over

Latent Space argues AI training pipeline stages—rewards, data, teachers, curricula, environments—are flipping from human-made to model-made simulation.

Latent Space's AINews essay traces how each component of AI training has turned synthetic since 2022: reward models (InstructGPT, RLAIF), synthetic pretraining data (Microsoft Phi, NVIDIA Nemotron-4 340B), model teachers (Alpaca, DeepSeek-R1 distillation), and self-generated curricula (Self-Rewarding Language Models, SPIN). In 2026 it highlights Karpathy's autoresearch loop—700 experiments yielding 20 kept improvements, cutting GPT-2 training time from 2.02 to 1.80 hours—and Z.ai's GLM-5.3 fully synthetic RL environment, judging, and verification stack. It frames these shifts as 'simulation': 10% worse but 100x cheaper and 10,000x faster than human equivalents.

Latent Space · 25d agoAI industry

Fine-tuning a 350M Model for Better Structured Outputs in 100 GRPO Steps

Hugging Face guide fine-tunes a 350M-parameter model with 100 GRPO steps to improve structured output reliability.

A Hugging Face blog post demonstrates fine-tuning a 350M-parameter model using GRPO (Group Relative Policy Optimization) with TRL over 100 training steps. The stated goal is more reliable structured outputs from small language models. No article body was available, so details beyond the title are limited.

Hugging Face Blog · 13d agoAI tools & infra

Environments as Scaffold: Enriching Feedback to Bootstrap Self-Evolving Agents in Long-Horizon Tasks

Researchers propose Feedback-Enriched Environments (FEEs) that reduce reward sparsity and improve RL training of Qwen3-based agents on SciWorld and BFCL.

The paper proposes shifting from agent-side warmup (SFT) to environment-side adaptation via Feedback-Enriched Environments to address severe reward sparsity in RL training of long-horizon LLM agents. A pilot study defines a feedback strategy that transitions from action guidance to observation enrichment in later training stages. Large-scale experiments on SciWorld and BFCL across Qwen3 model scales and GRPO, GSPO, and DAPO show consistent gains, plus stabilized training dynamics and proactive exploration.

Hugging Face daily papers · 9d agoAI research

DPRK APTs: Ted backdoor and curlRAT target South Korean media and automotive sectors

Rapid7 uncovered a DPRK-linked Linux toolkit using a HAProxy-embedded ted backdoor, SSH keylogger, and curlRAT against South Korean media and automotive firms.

Rapid7 Labs identified a previously undocumented framework attributed with medium confidence to DPRK actors, targeting South Korean automotive and media organizations likely since early 2025. The toolkit embeds a backdoor compiled into HAProxy 2.8.12 using its filter API, plus trojanized crond, agetty, atd, sshd, and polkitd, an SSH keylogger storing credentials under /var/lib/sshd/, and a curl-based RAT with a watchdog thread. It enables remote command execution, malicious script injection into served webpages (a watering-hole loop), credential harvesting, and long-term surveillance. Hardcoded C2s are associated with APT37 via ThreatFox, and exposed groupware portals and mail servers align with Kimsuky tradecraft; the initial access vector and any CVE remain unconfirmed.

Rapid7 Blog · 12d agoThreat actor in the wild1

Quantifying the Engagement Trap: Impact of Short-form Video Recommender Systems on Users with ADHD

A 302-participant study finds engagement-optimized short-form video recommenders cause disproportionate time blindness and distress for users with ADHD.

Researchers ran a stratified Prolific study with 302 participants comparing short-form video recommendation experiences with and without ADHD. Participants with ADHD reported significantly higher time blindness, post-usage regret, and emotional distress despite perceiving recommendations as similarly relevant. The paper proposes neurodiversity-aware, human-centered design interventions to mitigate these algorithmic harms.

arXiv cs.AI / cs.LG / cs.CL · 9d agoAI research

5 useful things you'll learn in my new post-training textbook (shipping now!)

Nathan Lambert's new RLHF and post-training LLM textbook covers PPO, GRPO, GSPO, CISPO and related techniques, freely available online.

Nathan Lambert's book 'Reinforcement Learning from Human Feedback: Aligning and Post-training LLMs' is now shipping from Manning. It covers policy-gradient algorithms including PPO, GRPO, GSPO, CISPO, and RLOO, plus loss aggregation, truncated importance sampling, asynchronous RL systems, and post-training topics like rejection sampling, outcome reward models, and on-policy distillation. The book is freely available online with a 12-hour course, codebase, and exercises.

Interconnects · Aug 10, 2026AI research

Iranian cyber targeting of dissidents, activists and journalists

UK NCSC, FBI, and Dutch AIVD expose CHOSEN BRICK spyware used by Iranian state actors against dissidents, activists, and journalists worldwide.

A joint advisory from the UK NCSC, FBI, and Dutch AIVD details CHOSEN BRICK, a Windows spyware family used by Iranian state cyber actors since at least 2025 against dissidents, activists, and journalists in the UK, US, and Netherlands. Actors build rapport on WhatsApp and Telegram impersonating known contacts or platform support, then deliver disguised payloads resembling apps such as Telegram, Norton, RunwayML, or fake MRI results. The malware persists via HKCU Run registry keys, adds Microsoft Defender exclusions, and uses a unique Telegram bot C2 per victim. Capabilities include screen capture, microphone recording, process enumeration, email and messaging data theft, file deletion, and system wiping; victim data has appeared on pro-Iranian leak sites.

NCSC UK · 1d agoThreat actor in the wild2

Zero-Click Grok Chat History Theft: Adversa AI Demonstrates Cryptographic Context Injection

Adversa AI's Cryptographic Context Injection bypasses AI guardrails using AES-encrypted payloads, enabling zero-click theft of Grok users' full chat histories.

Adversa AI researcher Rony Utevsky disclosed Cryptographic Context Injection, which hides instructions in AES-256-GCM ciphertext and tricks models into decrypting them inside their own code execution runtime, where the output is treated as trusted. Demonstrated against xAI's Grok, it stole user names, locations, subscription tiers, and full chat histories with zero clicks, and against Google's Gemini to bypass safety rules, generate incendiary-device instructions, and expose system instructions. Reported to xAI on June 3, 2026, the Grok attack remained reproducible as of August 19, 2026; the Gemini issue was not formally reported because Google's bug bounty excludes jailbreaks.

Security Affairs · 24d agoAI safety & security

You Can't Prefer Emotions You Don't Sample: Intensity Undershoot in DPO-Tuned LLMs

Study quantifies DPO-tuned LLMs undershooting requested emotional intensity, tracing the gap to candidate-pool extremity rather than conditioning format.

Conditioning an instruction-tuned LLM on continuous valence-arousal targets yields gain of only 0.26 for valence and 0.13 for arousal on Llama-3.1-8B, far below faithful control of 1.0. The authors attribute undershoot to neutral-heavy preference corpora like EmoBank and candidate pools lacking extreme affect, leaving DPO without extreme exemplars. Uniform target coverage with a hotter candidate pool raises valence gain to 0.40 on Llama-3.1-8B and 0.44 on Qwen3-8B, with modest in-distribution cost; arousal gains remain unstable across seeds.

arXiv cs.AI / cs.LG / cs.CL · 9d agoAI research

Iranian cyber spies used fake MRI scan results to hack ‘enemy of regime’

UK, US, and Dutch agencies expose CHOSEN BRICK spyware used by Iranian MOIS hackers to surveil dissidents, journalists, and activists via fake MRI lures.

The UK NCSC, FBI, and Dutch AIVD jointly warned that Iranian state-sponsored hackers deploy CHOSEN BRICK Windows spyware against dissidents, activists, and journalists since at least 2025. Operators build rapport over WhatsApp and Telegram, often posing as known contacts or tech support, then deliver malicious files disguised as an MRI scan or installers for Pictory, RunwayML, Norton, Telegram, Adobe Flash Player, and KeePass. The malware steals contacts, emails, and social media messages, captures screen content and microphone audio, adds Microsoft Defender exclusions, and uses per-victim Telegram bots for command and control. The FBI attributes the tradecraft to Iran's Ministry of Intelligence and Security, including the 'Handala Hack' persona, and stolen data has surfaced on pro-Iranian leak sites.

The Record · 1d agoThreat actor in the wild1

The OCUDU dApp Platform: An Open Runtime and E3 Interface for Real-Time AI-RAN

OCUDU open runtime lets third-party signed AI-RAN dApps run inside production 5G distributed units under three timing contracts, released as BSD-3 preview.

The OCUDU dApp platform provides an open runtime and E3 interface for executing signed AI-RAN applications inside a production 3GPP NR distributed unit, where prior dApp frameworks could only observe export streams. Modules run under three typed timing contracts: GPU receive-chain residency (Class A), the scheduler's 100 microsecond deadline (Class B), or non-blocking observer (Class C). On a GB10 gNB, dApps including an out-of-tree neural equalizer ran on a live cell without fallback. Platform, SDK, and a zero-hardware quickstart are public under BSD-3-Clause-Clear as a preview of the OCUDU AI-RAN Working Group 2.

arXiv cs.AI / cs.LG / cs.CL · 9d agoAI tools & infra1

Async GRPO with LoRA across HF Jobs: a bucket, a proxy, and no NCCL

Hugging Face blog describes running async GRPO reinforcement learning with LoRA across HF Jobs using a storage bucket and proxy instead of NCCL.

A Hugging Face blog post titled 'Async GRPO with LoRA across HF Jobs: a bucket, a proxy, and no NCCL' explains an asynchronous Group Relative Policy Optimization training setup using LoRA adapters distributed across Hugging Face Jobs workers. The architecture coordinates training through an object storage bucket and a proxy server, removing the need for NCCL collective communication. No full article text was available at classification time.

Hugging Face Blog · 6d agoAI tools & infra

Grok exfiltrates user data when malicious instructions are encrypted

Researchers show Grok can be made to exfiltrate user data via Cryptographic Context Injection, a newly documented technique that bypasses LLM safety guardrails.

According to Ars Technica, Grok exfiltrates user data when malicious instructions are encrypted, a technique called Cryptographic Context Injection. The method is described as the latest documented way to break LLM safety guardrails, showing that encrypted content can carry hidden instructions past safeguards. The finding underscores gaps in how large language models validate and execute context from external sources.

Ars Technica · Security · 27d agoAI safety & security1

Release Notes: Faster TI Investigations, Fresh Threat Research, and 650+ Threat Coverage Updates

ANY.RUN August release adds TI Lookup connections view, 81 behavior signatures, 16 YARA rules, 559 Suricata rules, and three new threat intelligence reports.

ANY.RUN released August product updates expanding its Threat Intelligence Lookup with a Connections block for pivoting between related observables (domains, IPs, URLs), JSON export for retrohunting and SIEM/NDR integration, and hidden whitelisted data by default. Detection coverage grew with 81 new behavior signatures, 16 YARA rules, and 559 Suricata rules covering malware execution, phishing, and C2 traffic. Three new Threat Intelligence Reports cover a US-focused RMM phishing campaign across 46 countries, the Mirage2FA phishing-as-a-service targeting Microsoft 365 (1,249 sandbox sessions, 9,332 potential compromise events), and a threat brief on OVERLORD RAT, CRPX0, and TRIBACK loader.

ANY.RUN · 13d agoTools1

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

Iranian spies hit Windows machines with Chosen Brick data-stealing malware

FBI, UK NCSC, and Dutch AIVD warn Iranian intelligence uses Chosen Brick spyware against dissidents, stealing contacts, emails, and messaging data.

A joint advisory from the FBI, UK NCSC, and Dutch AIVD says Iranian state cyber actors have used the Chosen Brick Windows malware since at least 2025 to surveil dissidents, activists, and journalists. Attacks begin with heavily researched WhatsApp and Telegram messages impersonating trusted contacts, tricking victims into opening fake installers resembling Pictory, RunwayML, Norton Antivirus, Telegram, Adobe Flash Player, and KeePass. The malware persists via the HKCU Run registry key, adds Microsoft Defender exclusions, uses victim-specific Telegram bots for C2, captures screen and audio, steals emails and Telegram/WhatsApp data, and can wipe systems.

The Register · Security · 1d agoThreat actor in the wild1

UK and allies expose spyware used by Iranian state actors to target dissidents, activists and journalists

Joint advisory details Iranian spear-phishing campaign deploying CHOSEN BRICK spyware to surveil dissidents, activists, and journalists across UK, US, Netherlands.

The NCSC (part of GCHQ), FBI, and AIVD jointly warned that Iranian state actors impersonate trusted contacts on WhatsApp and Telegram to deploy the CHOSEN BRICK spyware against dissidents, activists, and journalists worldwide. The Windows-only malware is persistent across reboots and collects contacts, emails, social media messages, screen captures, and microphone audio. Stolen personal details of some victims have been published on pro-Iranian leak sites. The FBI published complementary technical analysis, and the NCSC offers free cyber defence services for high-risk individuals.

NCSC UK · 1d agoThreat actor in the wild

PLC-DPO: Posterior Label Correction in Noisy and Ambiguous Preference Optimization

PLC-DPO corrects noisy preference labels during DPO by routing each pair as clean, flip, or tie using calibrated policy-reference margins.

PLC-DPO addresses reversed, weak, or ambiguous preference labels in Direct Preference Optimization by using the calibrated policy-reference margin as online evidence to route each pair's training signal as clean, flip, or tie. This actively corrects supervision direction and strength rather than only filtering suspicious examples. Across 57 dataset-model-benchmark cells, PLC-DPO achieves the best mean win rate of 60.5 versus 55.5 for the next-best method. Injected-noise and tie stress tests plus human disagreement analysis show the routing stays stable and distinguishes flipped from weakly directional pairs.

Hugging Face daily papers · 17d agoAI research

AVP-Inspect: Coordinated Cyber-Physical Testing for Privacy Analysis of COTS Apple Vision Pro Applications

AVP-Inspect automated testing finds 58% of 324 Apple Vision Pro apps show privacy violations, with over 60% of network traffic flows undisclosed.

Researchers built AVP-Inspect, a dynamic analysis framework combining custom hardware device control, 3D UI exploration, and a unified privacy taxonomy for Apple Vision Pro. Testing 324 App Store apps for 20 minutes each found 188 (58.0%) with at least one privacy violation. More than 60% of observed network traffic flows were not properly disclosed, extending prior XR privacy work beyond Android-based devices such as Meta Quest.

arXiv cs.CR · 8d agoResearch1

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

HuggingFace: Security.txt

Hugging Face published a security.txt file, prompting limited Hacker News discussion of the RFC 9116 disclosure standard.

Hugging Face's security.txt file, which lists its security contact and disclosure channels per the RFC 9116 standard, drew attention on Hacker News. The RFC 9116 standard lets organizations publish where and how security researchers should report issues, but the submission received only one comment.

Hacker News · securityupdated · 5d agofirst · 5d agoIndustry 2 sourcesHN 22↑ · 1 comments

Russia-Aligned Hackers Use GuardBreaker Prompt Injection to Disrupt AI Malware Analysis

Russia-aligned group UAC-0099 embeds GuardBreaker prompt injection in a VBScript comment to make AI malware scanners refuse analysis of a MATCHBOIL loader.

ESET identified a UAC-0099 VBScript used in an early-stage intrusion against a target in Ukraine that hides a safety-triggering comment (a question about building a nuclear weapon) intended to make AI code scanners refuse to continue analysis. The script downloads MATCHBOIL, a loader associated exclusively with UAC-0099, alongside familiar anti-analysis checks for IDA and Wireshark. The technique turns the AI triage process itself into the attack target, risking missed detections or benign misclassification of malicious samples.

Cyber Security News · 5d agoThreat actor in the wild 3 sources

Pegasus Zero-Click Exploit Infects Serbian Student Activist's iPhone

Citizen Lab and SHARE Foundation confirm a Serbian student activist's iPhone was infected with NSO Group Pegasus via a zero-click iMessage exploit.

Forensic analysis found high-confidence infection indicators on the activist's iPhone during December 2025 and January 2026, using an iMessage zero-click exploit the Citizen Lab believes was patched as of iOS 18.4.1, released April 2025. The target was among at least 14 Apple Threat Notification recipients in Serbia's student movement, civil society, and opposition politics documented by the SHARE Foundation. Targeting occurred ahead of key 2026 election cycles; Amnesty Tech also confirmed a new NoviSpy version on another student movement member's device.

Infosecurity Magazine · 13d agoThreat actor in the wild

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

Attackers impersonate popular AI brands to spread malware

Sophos documented 38 MDR cases where attackers impersonated AI brands like Claude and Perplexity to deliver infostealers and backdoors.

Sophos X-Ops analyzed 12 months of MDR cases and confirmed 38 incidents involving AI. Software impersonation accounted for 30 cases, with Claude impersonated in 26; fake installers used an 'InstallFix' technique delivering mshta commands, in-memory payloads, and process hollowing. Malicious browser extensions posing as AI assistants, including a fake Perplexity extension with 10,000 installs, acted as infostealers. In one case, attackers used a Claude coding agent to develop a Rust remote access trojan communicating over Slack after an SQL injection compromise.

Help Net Security · 26d agoThreat actor in the wild

Hackers Abuse Google CAPTCHA, WebDAV and BNB Smart Chain to Deploy Credential-Stealing Malware

Cisco Talos details ClickFix campaigns abusing fake Google CAPTCHA prompts, WebDAV and BNB Smart Chain to deploy the Amatera infostealer.

Cisco Talos identified a multi-stage campaign, first observed in April 2026 when a Ukrainian government organization executed a disguised DLL named verification.google from a WebDAV path. The chain combines ClearFake JavaScript injected via malicious Cloudflare Workers, EtherHiding payloads stored in BNB Smart Chain contracts, ClickFix social engineering, and WebDAV-hosted DLL loaders to deliver the Amatera (ACR Stealer) infostealer. The Amatera configuration contained over 400 collection entries targeting browsers, messengers, crypto wallets, password managers, FTP and VPN tools, hunting for .kdbx, .p12, .pfx and .pem files. The pf.ch branch deploys ZigCryptoStealer, an EDR-terminating vulnerable driver and Go-based reverse TCP proxies, while the verification.google branch installs NetSupport Manager, supporting moderate-confidence attribution of the UAT-10820 activity to a Russian actor.

GBHackers · 7d agoMalware in the wild