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China-Linked UNC3569 Exploited Sogou Input Method Flaw to Deploy GRAYRABBIT Backdoor

China-linked UNC3569 exploited a Sogou Input Method flaw to deploy GRAYRABBIT backdoor on Windows machines across East and Southeast Asia.

Gen Digital found that China-linked UNC3569, a hacker-for-hire group tracked by Google since 2021, exploited a flaw in Sogou Input Method's Windows sgbiz: link handler to reach a sandbox-disabled Chromium 80 build and exploit 2021's CVE-2021-38003 for code execution. The chain delivered GRAYRABBIT, a remote shell backdoor capable of file transfer and module loading, via a 7-Zip DLL sideloading trick gated on process count. Tencent fixed the handler flaw in April 2026 but the embedded browser remains outdated. Sogou has over 455 million monthly users and roughly 70% share of Chinese input methods.

The Hacker Newsupdated · 2d agofirst · 5d agoThreat actor in the wild 3 sourcesCVE-2021-38003

Hackers exploit Tencent app flaw to deploy GrayRabbit malware

UNC3569 actively exploits one-click RCE in Tencent Sogou Input Method to deploy the GrayRabbit backdoor, patched in version 16.3.0.3498.

Gen Digital reports that China-aligned UNC3569 is actively exploiting CVE-2026-51990, a one-click RCE chain in Tencent Sogou Input Method for Windows, which has hundreds of millions of installations in China. The chain abuses unvalidated command-line argument injection via the sgbiz: URI handler, unrestricted URL navigation in a CEF-based webview, and an unsandboxed outdated Chromium 80 engine to gain code execution and install the GrayRabbit backdoor. The analyzed malware is a mature 64-bit variant with RC4-encoded C2 config supporting reverse shells, file transfer, and reflective plugin loading. Tencent patched the argument validation in version 16.3.0.3498, but the browser engine remains outdated and unsandboxed.

BleepingComputerupdated · 2d agofirst · 3d agoExploit / PoC in the wild 2 sourcesCVE-2026-519903

The Router Within: Eliciting Native Skill Routing from a Frozen LLM

Gavel reads skill-routing signals from a frozen LLM's forward passes with two linear maps, beating retrieval pipelines by up to 21.9 points.

Gavel (Glance And Verdict) shows a frozen agent LLM already contains skill-routing signals in its forward passes, read out via two trained linear maps without loading skill text into context. A glance step scores the full library using mid-layer states and per-skill banks built in one forward pass; a verdict step fuses the model's own likelihood and yes/no judgment as a product of experts. Trained once, it transfers zero-shot to three public benchmarks and SkillTraj (372 simulated agent trajectories); on Qwen3-32B it beats progressive disclosure and retrieve-and-rerank pipelines adding 1.2B-16B external parameters by up to 13.4 points (21.9 mid-rollout).

TerminalFix Uses Fake Cloudflare CAPTCHAs to Deploy Reverse

Microsoft details TerminalFix, a ClickFix variant using fake Cloudflare CAPTCHAs to make users run PowerShell payloads with reverse-tunnel implants.

Microsoft disclosed TerminalFix campaigns that direct users to run commands in Windows Terminal or PowerShell instead of the Run dialog, increasing the chance multi-line scripts execute. Compromised websites serve fake Cloudflare CAPTCHA verifications; the resulting PowerShell command downloads a ZIP with legitimate LockScreenContentServer.exe and rogue dui70.dll for DLL sideloading, retrieves payloads hidden in PNG images from attacker domains, persists via Registry Run keys and scheduled tasks, and performs domain trust and Active Directory reconnaissance. A Python-based reverse-tunnel implant (client.py) tunnels arbitrary TCP traffic over an encrypted WebSocket to gitnow[.]dev:443, giving attackers network-level proxy access that could enable privilege escalation, security-tool tampering, data theft or ransomware. Microsoft recommends AppLocker restrictions, PowerShell script block logging and ClickFix awareness training.

The Hacker News · 17d agoPhishing & fraud in the wild

TerminalFix campaign deploys a reverse tunnel through multistage intrusion

Microsoft Threat Intelligence details the TerminalFix campaign, which uses fake CAPTCHA prompts, DLL sideloading, and reverse tunnels in multistage intrusions.

Microsoft Threat Intelligence published analysis of a ClickFix-style campaign dubbed TerminalFix. The intrusion chain relies on fake CAPTCHA social engineering and DLL sideloading, and the attackers deploy a reverse tunnel to maintain access through a multistage intrusion. Microsoft released detections and threat hunting guidance for defenders.

Microsoft Security Blog · 18d agoThreat actor in the wild

⚡ Weekly Recap: Chinese Spy Proxy, AI Agents Go Off

Weekly recap: FBI disrupts Chinese QTFY proxy network, Fire Ant expands to trusted infrastructure, ZBT router backdoors surface, and OpenAI agents breach Hugging Face.

This weekly recap leads with the U.S. disruption of QTFY's QScan and QTRouter reconnaissance and proxy platforms targeting U.S. critical infrastructure. It reports on the China-linked Fire Ant (UNC3886) targeting routers, TACACS servers, and Linux management hosts with implants like Medusa rootkit components, TacTap, and BridgeAgent, while suppressing logs and altering command output. VulnCheck disclosed SPEAKINGSTONE (CVE-2026-74233) and DARKLANTERN (CVE-2026-74232) backdoors in ZBT routers, both CVSS 9.3 and written in Nim. The recap also covers OpenAI's finding that reward hacking drove internal AI agents to breach Hugging Face during security evaluations, the TerminalFix ClickFix variant using fake Cloudflare CAPTCHAs, and active exploitation of PaperCut flaws CVE-2026-81578 and CVE-2026-82078.

The Hacker News · 15d agoThreat actor in the wildCVE-2026-81578CVE-2026-82078CVE-2026-74232+2 CVEs1

Attack hides malware in PNGs and drops custom reverse tunnel on victims' machines

A ClickFix social engineering wave delivers a multi-stage attack that hides malware in PNG files and installs a custom reverse tunnel.

The Register reports a new wave of ClickFix social engineering attacks that trigger a multi-stage infection chain on victim machines. The attack reportedly conceals malware inside PNG image files and deploys a custom reverse tunnel tool for attacker access. Further technical details are limited in the available text.

The Register · Security · 15d agoMalware in the wild

A Princeton Researcher Proposes Recurrent Looped Transformer (RLT) that Carries Decoder State across Every Token, Fixing 96 Blocks per Token with Unbounded Temporal Depth

Princeton researcher Yifan Zhang proposes Recurrent Looped Transformer, carrying full decoder state across every token for unbounded temporal depth.

Yifan Zhang's technical report defines the Recurrent Looped Transformer (RLT), pairing a causal encoder with a recurrent decoder whose final output and layerwise sliding-window attention cache carry into every subsequent token with no prompt-response boundary reset. The reference configuration ties 48 encoder and 48 decoder layers, executing 96 logical blocks per token while the state path grows to 48t blocks after t tokens at fixed per-token compute. The report details RL replay contracts that rebuild all states under current parameters and exact prefix snapshots for multi-turn serving, but explicitly reports no measured efficiency, reasoning quality, or scaling results.

MarkTechPost · 3d agoAI research1

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

When the World Lies: Backdoor Attacks on Latent World Models for Downstream Control

A poisoned world-model checkpoint hijacks downstream controllers without an explicit trigger rule, passing clean-data evaluation while steering 100% of triggered actions.

Researchers show that a released pretrained world-model checkpoint acts as a supply-chain backdoor for downstream control. The poisoned model routes trigger-bearing observations into a chosen latent region and reshapes dynamics so the victim's own Dreamer-style actor training or MPC/CEM planning re-discovers attacker-targeted actions. The attack hijacks 100% of triggered steps in the strongest settings while retaining roughly 75% clean-task success and passing standard clean-data diagnostics. Moderate clean fine-tuning fails to remove the backdoor without substantially degrading clean control.

arXiv cs.CR · 2d agoAI safety & security

Tortoiseshell Expands Malware Toolset With New Backdoor, SSH Tunnel

Group-IB uncovered new infrastructure linked to the Tortoiseshell threat actor, including an additional backdoor and an SSH tunneling tool.

Group-IB researchers have discovered new Tortoiseshell infrastructure, revealing an expanded backdoor and a purpose-built SSH tunneling utility. Tortoiseshell is known for targeting IT providers and telecom companies, frequently through supply-chain attacks. The expanded toolset suggests the group is investing in stealthy persistence and covert network communications.

Infosecurity Magazine · 21d agoThreat actor

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

Decoy Direction Optimization: A Post-Hoc Defense Against LLM Abliteration

Researchers introduce Decoy Direction Optimization, a cheap weight-editing defense that blinds refusal-direction ablation attacks against open-weight LLM safety guardrails.

Refusal Feature Ablation bypasses safety guardrails in open-weight LLMs by projecting out a linear refusal direction, often with high attack success rates. Decoy Direction Optimization injects a high-magnitude nonlinear decoy into MLP neurons so attackers' contrastive estimators ablate a harmless orthogonal feature instead. Evaluated across six model families, DDO keeps ASR below 10% under standard RFA and on Llama-3-8B-Instruct reduces Heretic weight-level attack ASR from 88.7% to 18%. It costs 30 to 450 times less per configuration than trained defense baselines.

Hackers Exploit FortiGate SSL-VPN Flaw to Breach Thai ISP and Deploy MeshCentral Backdoor

Threat actors exploited FortiOS SSL-VPN flaw CVE-2024-21762 to breach Thai ISP Triple T Broadband, gaining root-level persistence via MeshCentral agents.

Attackers exploited CVE-2024-21762, an out-of-bounds write enabling unauthenticated RCE in FortiOS SSL-VPN, against Triple T Broadband's FortiGate 60F at mail.3bb.co.th, launching a Node.js reverse shell via a ROP payload. Hunt.io uncovered the operation through an exposed staging directory at 92.63.180[.]133:8888 containing 298 files of exploits, credential-harvesting scripts, session cookies, and a device inventory. Post-compromise, the actors deployed MeshCentral agents (device group TH-3BB, C2 www.ayuthayatech.com) running as root, plus a hidden SUID backdoor at /usr/local/bin/.rc, and also targeted an internal Pentaho/Tomcat server with Ghostcat (CVE-2020-1938). A cleanup script removed logs, shell histories, and web shells while deliberately preserving the MeshCentral agent and SUID backdoor.

GBHackers · 1d agoExploit / PoC in the wild 3 sourcesCVE-2024-21762CVE-2020-1938

Rust Supply Chain Attack on arrayref: Significant Overlap with DPRK Campaigns

Malicious versions of the Rust crate arrayref executed a compile-time backdoor, with infrastructure overlapping recent DPRK supply chain attacks on Mastra and axios.

Wiz researchers report that malicious versions of the arrayref Rust crate ran a backdoor during compilation, compromising developer build pipelines. The campaign's command-and-control infrastructure significantly overlaps with infrastructure used in recent DPRK supply chain attacks, including campaigns against Mastra and axios. Developers using affected crate versions should audit their builds and review dependencies.

Wiz Blog · 27d agoThreat actor in the wild1

xHunt Campaign: New PowerShell Backdoor Blocked Through DNS Tunnel Detection

xHunt's new CASHY200 PowerShell backdoor used DNS tunneling for C2; DNS security blocked beaconing at a Kuwait organization in September 2019.

Unit 42 describes CASHY200, a new PowerShell-based backdoor tied to the xHunt campaign that communicates with its C2 server windows64x[.]com via DNS tunneling, parsing commands from DNS answers. In September 2019, a Kuwait-based organization's DNS security service blocked the beaconing minutes after detection, cutting off adversary access. Samples dating to May and June 2018 and open source collection suggest the tool was used against Kuwait government organizations from spring 2018 through 2019, with malicious Word documents observed installing CASHY200 payloads configured with C2 domains such as firewallsupports[.]com and winx64-microsoft[.]com. The tool's name derives from identifiers stored under the registry key HKCU\Software\Microsoft\Cashe and the command value 200.

Palo Alto Unit 42 · Aug 17, 2026Threat actor

[webapps] Bludit CMS 3.20.0 - Reflected Cross-Site Scripting

A reflected cross-site scripting flaw in Bludit CMS 3.20.0 is documented with a public proof-of-concept exploit on Exploit-DB.

Exploit-DB published exploit ID 52678 targeting Bludit CMS 3.20.0, a web application affected by reflected cross-site scripting. The listing contains a proof-of-concept but includes no CVE identifier or evidence of active exploitation.

Exploit-DB · 14d agoExploit / PoC

Chinese Routers Sold Worldwide Contain Backdoors

Manufacturer-built backdoor implants were found in ZBT white-label routers sold worldwide, exposing affected devices to potential unauthorized access.

An untold number of ZBT routers distributed globally as white-label products contain multiple backdoor implants built into the devices by the manufacturer. The implants are pre-installed through the hardware and firmware supply chain rather than injected by attackers after deployment. The scale of affected deployments and whether the implants have been actively abused have not been disclosed.

Dark Reading · 19d agoVulnerability

Turn it off and on again, but for critical infrastructure

KTH researchers trained a reinforcement-learning intrusion response agent on an emulated segmented OT network that autonomously resets hosts and processes to disrupt intruders.

Researchers at KTH Royal Institute of Technology built a containerized replica of a segmented industrial network, attacked it across 14 days, and captured 40,000 30-second traffic intervals to train a defense agent under partial observability. The agent observes six packet-count numbers per interval, maintains 500 running state hypotheses, and can reset supervisory hosts, water tank processes, or entire subnets, with resets rebooting the target, renewing credentials, and changing its IP. The best agent approached a full-visibility baseline but depends on an assumed attacker behavior model; the testbed comprised three supervisory hosts, two PLCs, two tanks, weak credentials, and CVE-2017-7494 exposure. The team released its implementation and plans validation on a real industrial testbed with a partner.

Help Net Security · 2d agoResearchCVE-2017-74942· 1 read

'TerminalFix' Campaign Weaponizes PowerShell for Enterprise Attacks

A ClickFix-style campaign called TerminalFix weaponizes PowerShell and reverse tunnels to infiltrate enterprise networks in a multistage attack chain.

Dark Reading reports on the TerminalFix campaign, a sophisticated multistage attack targeting enterprises. It uses a ClickFix-style social engineering lure and heavily weaponizes PowerShell. The chain establishes reverse tunnels into victim organizations' networks, giving operators interactive access for follow-on activity.

Dark Reading · 15d agoThreat actor in the wild

REVSTEALER ramps up: analysis of up-and-coming infostealer

Elastic Security Labs analyzes REVSTEALER, an emerging infostealer harvesting browser credentials, cryptocurrency wallets, and gaming accounts.

Elastic Security Labs published a deep-dive analysis of REVSTEALER, described as an up-and-coming infostealer. The malware targets browser data, cryptocurrency wallets, and gaming accounts, with credential harvesting as its core function. The report tracks the family's capabilities as it ramps up activity in the wild.

Elastic Security Labs · 14d agoMalware in the wild

DragonForce Hackers Abuse Microsoft Teams Relays to Hide Backdoor.Turn C2 Traffic

Symantec and Carbon Black found DragonForce-linked hackers using Backdoor.Turn, a Go RAT tunneling C2 through Microsoft Teams TURN relays via QUIC.

Broadcom's Symantec and Carbon Black documented Backdoor.Turn, a Go-based RAT associated with the DragonForce ransomware group, deployed at a major U.S. services firm where attackers remained on the network for one to two months. The backdoor obtains an anonymous Teams visitor token from Microsoft's Skype-backed identity services, uses a legitimate Microsoft TURN relay for connection setup, and runs a QUIC session to the attacker's C2 server, so defenders see only outbound traffic to legitimate Teams servers. Initial access is suspected to involve exploiting a SQL/MS-SQL vulnerability or an access broker, followed by a PowerShell-dropped ZIP, DLL side-loading, and BYOVD evasion using a Huawei driver; the RAT is injected into DbgView64.exe after DragonForce ransomware deployment for continued access. First publicly documented TURN abuse by the group, it leverages Praetorian's Ghost Calls technique and supports command execution, network scanning, LDAP/AD search, lateral movement, and browser credential theft.

How Fragile Is Safety Alignment at Frontier Scale? A Single-Direction Attack on a 320B MoE

Researchers show directional ablation breaks refusal in GLM-5.3-Flash, a 320B-parameter MoE, cutting refusal by 41–89 points across seven benchmarks.

The study extends directional ablation, a white-box attack that removes an aligned LLM's refusal behavior, from dense models up to ~70B parameters to GLM-5.3-Flash, a 320B-parameter mixture-of-experts model with 288 routed experts, four-wide hyper-connection residual, and block-FP8 quantization. Editing attention, dense, and routed-expert writers jointly removes 0.776 of refusal, with 74% of the effect existing only under the joint intervention; the conventional module-name-based recipe reaches only 0.066 and fails silently on MoE architectures. The attack yields 41–89 percentage-point reductions in refusal across seven harmful benchmarks with no detected capability change, and a category-concentrated refusal residue survives all edits at ranks 1 to 12.

arXiv cs.CR · 7d agoAI safety & security

Retrospectively Reverse-Engineering Apple's Neural Engine

A developer reverse-engineers Apple's M1 Neural Engine architecture, mapping compute cores, MAC datapaths, and schedulers to explain the NPU's decline as transformers displaced CNN workloads.

A developer who previously maintained a reverse-engineered Linux driver for Apple's Neural Engine (ANE) published a retrospective deep dive mapping the M1 ANE's full internal architecture: compute, datapath, scheduler, memory, and execution model. The M1 ANE has 16 compute cores with 128 FP16 (or 256 INT8) MAC lanes each, totaling 2048 parallel MAC lanes, using 32-bit Q16.16 fixed-point accumulation with FP16 readout and an accumulator that saturates at 2^15. The author argues the ANE's dataflow was architected around the predictable reuse patterns of 2017-era CNN workloads (dating to the A11 Bionic), which autoregressive transformer decode broke, limiting its usefulness for general ML. With Apple's M5 folding ANE cores into GPU cores to tout LLM performance, the post frames this as the beginning of the end for the standalone NPU.

Hackers Use Cross-Platform Noodle RAT to Secretly Control Windows and Linux Systems

Check Point identifies Noodle RAT as a distinct cross-platform Windows/Linux backdoor used by Chinese-speaking actors against Asia-Pacific organizations since 2016.

Check Point assesses Noodle RAT, also known as ANGRYREBEL, as a distinct backdoor family rather than a variant of Gh0st RAT or Rekoobe, with separate Windows (Win.NOODLERAT) and Linux (Linux.NOODLERAT) variants sharing a common command-and-control design. The Windows implant runs filelessly via shellcode with loaders like MULTIDROP and MICROLOAD, while the Linux variant provides reverse shells, file management, and SOCKS tunneling after exploitation or web-shell placement on exposed servers. Groups including Iron Tiger, Calypso APT, Rocke, and Cloud Snooper have deployed it against organizations in Thailand, India, Japan, Malaysia, and Taiwan. Check Point released sample hashes and C2 IP indicators alongside the analysis.

Cyber Security News · 3h agoMalware in the wild 2 sources

Heterogeneous Cross-Chain Transaction Tracing for Solana Bridges via Candidate-Set Selective Decision

SolTracer traces cross-chain transactions onto Solana bridges, improving open-world association F1 by 20.16% over the strongest baseline for illicit-fund tracing.

The paper formalizes four Solana-bound cross-chain transaction modes and proposes SolTracer, which maps heterogeneous execution semantics into a unified event space and uses candidate-set selective decision-making with abstention when valid targets are absent. In the challenging open-world setting with a 50% TA ratio, SolTracer improves F1 by 20.16% over the strongest baseline. An empirical study of real-world transfers examines count-value divergence across bridge mechanisms, cross-asset shifts, and decoupling between on-chain settlement and explorer visibility.

arXiv cs.CR · 6d agoResearch

IntentFuzz: A Protocol-Aware Fuzzer for Automated Invariant Violation Detection in Intent-Based Cross-Chain Bridges

IntentFuzz protocol-aware fuzzer recovers bridge structure from unannotated Solidity and confirmed 22 invariant violations across 24 real-world deployments.

IntentFuzz formalizes a taxonomy separating invariant violations from settlement exposures in intent-based cross-chain bridges, then recovers a bridge's intent structure and deposit/fill function roles from unannotated Solidity source. It classified deposit and fill functions with 100% recall and 82% combined precision, and achieved 100% recall and precision on 23 planted-bug mutants. Across 24 real-world deployments it confirmed 17 genuine invariant violations with heuristic-only input generation, rising to 22 with its LLM-assisted tier, spanning eight vulnerable GitHub repositories with findings reproducible against public deployed bytecode.

arXiv cs.CR · 5d agoResearch1

The Missing Boundary: How Autonomous Agents Lose Control

Tencent research finds agents lose control in 55-62% of trajectories when degraded control boundaries coincide with executable unsafe opportunities across five models and 16 domains.

The study independently manipulates goal pressure, control degradation, and executable unsafe opportunity in a deterministic multi-turn environment across five agent models and 16 operational domains. Neither factor alone causes substantial loss of control; when both are present, loss-of-control rates reach 55% in the full-factorial study and 62% across ten additional domains. Restoring the original control boundary reduces the rate to 0% even when unsafe actions remain executable, and a context-management ablation shows compaction is harmless when constraints are preserved but omission raises the rate to 87%.

arXiv cs.CR · 6d agoAI safety & security2