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PuzzleMask: Abusing Plain Prose as a Covert AI Attack Vector

Check Point details PuzzleMask, a plain-prose technique that bypasses LLM gatekeeper policy checks, letting hidden payloads reach target models unreviewed.

Check Point Research describes PuzzleMask, a prompt-crafting technique that hides policy-violating payloads inside plain-English prose wrappers, bypassing quick LLM-based policy checks without emojis, Base64, or invisible formatting. The researchers tested 23 automated prompts against gatekeepers including GPT-4o-mini, GPT-OSS-Safeguard 20b, Claude 3 Haiku, and Llama Guard 3, and all were classified as safe despite policies that flagged the plain versions. When submitted to GPT-5 in thinking-high mode with a Python interpreter, the target model extracted and acted on the payload in over 90% of trials. The technique is not itself a jailbreak but can carry a jailbreak prompt as payload; mitigations include input paraphrasing, hardened gatekeeper policies, and output monitoring.

Check Point Researchupdated · 5d agofirst · 6d agoAI safety & security 2 sources

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

Hackers Can Hide Malicious AI Commands Inside Normal English to Bypass Security Filters

Check Point's PuzzleMask technique hides malicious prompts in ordinary English that fast gatekeeper models miss but high-reasoning downstream models execute.

Check Point researchers disclosed PuzzleMask, a technique concealing policy-breaking instructions in natural-language prose without encodings or invisible characters. Fast screening models classified all 23 crafted wrappers as safe, while a high-reasoning model recovered and acted on the hidden instruction in 17 of 18 tests (94.4%). The gap stems from capability imbalance between gatekeeper and target models, with defenses including paraphrasing untrusted input, stricter self-referential wording rules, and output/tool-call monitoring.

Cyber Security News · 5d agoAI safety & security1

JavaScript obfuscation: From party trick to phishing kit

Cisco Talos explains JavaScript obfuscation techniques used by phishing kits and the approaches researchers use to reverse them.

Cisco Talos published an educational walkthrough of JavaScript obfuscation as used in modern phishing kits. The piece covers why analysts deobfuscate malicious scripts and outlines several practical approaches to reversing obfuscated code. The techniques help defenders unpack phishing kit payloads during investigations.

Cisco Talos · 20d agoResearch

Cardinal RAT Sins Again, Targets Israeli Fin

Unit 42 documents updated Cardinal RAT attacks against Israeli FinTech firms, using BMP steganography, MD5-hash obfuscation, and process injection to hinder analysis and detection.

Unit 42 tracked a series of attacks using an updated Cardinal RAT (version 1.7.2) targeting the Israeli financial technology sector. The .NET loader hides a second-stage DLL inside an embedded BMP image decrypted with a single-byte XOR key, and the payload renames functions, methods, and variables to MD5 hashes for obfuscation. The malware installs a startup-folder LNK file and injects its final payload into RegSvcs.exe or RegAsm.exe, communicating with affiliatecollective[.]club over port 443. A possible relationship with the EVILNUM JavaScript malware used against similar organizations was also noted.

Palo Alto Unit 42 · Aug 17, 2026Malware1

Trends in Web Threats in CY Q2 2022: Malicious JavaScript Downloaders Are Evolving

Unit 42 detected 751,000 landing URL incidents in Q2 2022 and documented malicious JavaScript downloaders evolving to evade detection.

Unit 42 detected 751,331 landing URL incidents (253,644 unique) and 1,744,629 malicious host URL incidents (256,844 unique) from April through June 2022. Total landing URL incidents rose compared with Q1 2022, and unique host URL incidents grew 42%, indicating attackers deploying more variants. The report includes a case study of a JavaScript downloader campaign demonstrating new evasion techniques. Personal sites, blogs, and business sites were the top apparently benign entry points.

Palo Alto Unit 42 · Aug 17, 2026Research

Attackers conceal phishing lures using invisible Unicode characters

Threat actors use invisible Unicode characters (ASCII smuggling) to hide phishing lures and evade email security filters.

Threat actors have adopted the ASCII smuggling technique in phishing campaigns, embedding invisible Unicode characters in emails to conceal malicious lures. The approach is designed to evade email security filters that scan for visible phishing indicators. The report gives no victim counts or named campaigns.

BleepingComputer · 10d agoPhishing & fraud in the wild

The extension you never installed: KREMLIN forges Chrome's own integrity checks to steal banking sessions

Elastic details KREMLIN, a Brazilian banking malware whose malicious Chrome/Edge extension forges Chromium integrity checks to steal sessions.

Elastic Security Labs tracked operation REF9334 and its KREMLIN toolkit, a Brazilian banking malware campaign impersonating twelve banks across seven campaigns since May 2025. The infection chain uses multi-stage obfuscated JavaScript loaders with sandbox checks (file and process counting), scheduled-task persistence, and an Ethereum smart contract acting as a dead-drop resolver for C2 and payload URLs, abusing Archive.org for hosting. The malicious browser extension bypasses Chromium integrity mechanisms by manipulating Secure Preferences and regenerating required HMACs and App-Bound encrypted hashes. Threat Command disrupted over 1,500 infections by registering the kill-switch canary domain.

Elastic Security Labs · 2d agoMalware in the wild

ReCAST: Restoration-aware Cascaded Stage-wise Training for Obfuscated SMS Risk Classification

ReCAST distills a large teacher model's de-obfuscation ability into smaller models for robust classification of obfuscated Chinese SMS fraud messages.

The paper proposes ReCAST, a restoration-aware cascaded stage-wise training framework for classifying obfuscated Chinese SMS messages. It distills a large teacher model's de-obfuscation capability into a smaller deployable student by supervising obfuscated span detection, obfuscation type prediction, and text restoration, then uses the student for risk classification. On an internally constructed real-world Chinese SMS benchmark, ReCAST substantially outperforms directly trained baselines under obfuscation, targeting production latency and throughput constraints.

arXiv cs.CR · 12d agoResearch

Hackers Abuse Google Sheets as C2 in ClickFix Attacks to Steal Cryptocurrency

Cisco Talos tracks a ClickFix crypto-theft campaign using Google Sheets as C2 to swap deposit addresses in Chrome.

Cisco Talos uncovered a cryptocurrency theft campaign that abuses Google Sheets and the Google Visualization API as a covert C2 channel, delivering obfuscated JavaScript into victims' Chrome browser sessions via ClickFix-style social engineering. Victims are lured with a fake "API Logic Flaw" report promising 25-38% bonuses on SimpleSwap and SwapZone swaps; the injected payload acts as a browser-based web skimmer that replaces deposit addresses, overrides the fetch API, and hijacks the clipboard. Later variants use the legitimate Tampermonkey extension with a user script for persistence without OS-level compromise. Talos identified 49 Bitcoin wallets, with 24 reused addresses receiving about 0.159 BTC (~$10,000) before mixing through more than 3,000 addresses.

GBHackers · 7d agoPhishing & fraud in the wild

Once popular for attacking AI, ASCII smuggling is embraced by spammers

Spammers adopt ASCII smuggling—invisible Unicode tag characters—to evade email filters, with Microsoft Defender detections spiking to 2.5 million per day.

ASCII smuggling hides text in Unicode tag characters (e.g., U+E0041 for "A") that are invisible to humans but readable by LLMs and text processors. The technique gained attention as a stealthy prompt-injection vector and is now used by spammers to obfuscate keywords from email detectors. Microsoft reported Defender for Office smuggling detections jumped from roughly 21,000 per day to over 1.3 million in early February, reaching 2.5 million within four days, before falling sharply in mid-May.

Ars Technica · Security · 11d agoPhishing & fraud

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

Campaign Evolution: pseudo

Unit 42 traces the pseudo-Darkleech campaign's 2016 shift from Angler to Neutrino to Rig exploit kits and rotating ransomware payloads.

Unit 42 documents how the pseudo-Darkleech exploit kit campaign evolved through 2016, switching from Angler EK to Neutrino EK in June and to Rig EK in September after Neutrino ceased operations. Payloads rotated from TeslaCrypt to CryptXXX, CrypMIC, and finally Cerber ransomware by October 2016. Injected script on compromised websites changed from 12,000-18,000 character obfuscated blocks to short, unobfuscated hidden iframes starting July 1, 2016.

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

Understanding the Security Boundary of Obfuscation-based On-Device LLM Protection

Researchers formalize obfuscation primitives for TEE-protected on-device LLMs and show a Collapse attack breaks ArrowCloak, TSQP, and LoRO, then extend the boundary.

The paper formalizes obfuscation primitives for TEE-Shielded LLM Partition (TSLP) schemes that offload computationally intensive layers from a Trusted Execution Environment to external GPUs. A novel primitive-guided attack, Collapse, demonstrates a shared vulnerability in prominent published methods including ArrowCloak (Security'25), TSQP (S&P'25), and LoRO (NeurIPS'25). The authors then introduce two new obfuscation primitives and integrate them with existing constructs to formulate an extended security boundary (O_ext).

arXiv cs.CR · 7d agoAI safety & security

Rare Not Random Using Token Efficiency for Secrets Scanning

Researcher proposes token efficiency (string length divided by BPE token count) as a better post-regex filter than entropy for secrets scanning, validated on CredData.

The post explores whether Byte-Pair Encoding tokenization can replace Shannon entropy as the primary filter for candidate secrets captured by regex in tools like Gitleaks. It defines 'token efficiency' as string length divided by token count under the cl100k_base tokenizer; secret-like strings such as GitHub tokens tokenize into many small tokens and score low, while natural text scores high. Evaluating labeled secrets from the CredData dataset shows a usable separation, with roughly 2.5 suggested as a minimum cutoff versus Gitleaks' 3.5 entropy threshold. The technique is positioned as a post-regex filtering step rather than a standalone detector.

Lobsters · security · 4d agoResearch

Upatre Continued to Evolve with new Anti

Unit 42 analyzes an undocumented Upatre downloader variant with VM detection via process hashing, packed code, disabled Windows defenses and Namecoin .bit C2 domains.

Unit 42 analyzed an Upatre downloader variant compiled in December 2016 that went largely undetected by automated systems, featuring heavy code flow obscuration, on-demand decryption of network communications, and novel virtual machine detection. The sample enumerates running processes, computes CRC32 hashes XORed with a hard-coded key, and sleeps if analysis-related processes such as vmtoolsd.exe or python.exe are found. It masquerades with Google Chrome icons, disables Windows Defender, Firewall and other security services, injects code into msiexec.exe, and resolves .bit Namecoin domains like bookreader[.]bit via hardcoded OpenNIC DNS servers over TCP.

Palo Alto Unit 42 · Aug 17, 2026Malware1

Stealing AI Reasoning Traces

Researchers demonstrate a decryption jailbreak that extracts encrypted reasoning traces from Anthropic, OpenAI, and Google LLM APIs via weaker sibling models.

The paper exploits the fact that encrypted chain-of-thought blocks returned by LLM providers are interchangeable across sessions, users, and models within a provider's ecosystem. Injecting an encrypted trace into a weaker, less-safeguarded model from the same provider forces it to output the trace in plaintext, bypassing anti-distillation mechanisms. Decoding 315,320 reasoning blocks scraped from public repositories recovered 367 PII artifacts and 182 credentials, showing large-scale private data leakage. The flaw also enables hidden hazardous information disclosure and invisible prompt injections embedded in encrypted blocks; mitigations were proposed after responsible disclosure.

Schneier on Security · 8d agoAI safety & security

Impersonating IT support: how threat actors turn a remote session into enterprise-wide access

Microsoft details Teams IT-support impersonation campaigns deploying Node.js implants, AD reconnaissance, and WinRM lateral movement toward domain controllers.

Microsoft Threat Intelligence describes a human-operated campaign where attackers impersonate IT/helpdesk staff via Microsoft Teams external collaboration, talk users into granting remote sessions, and use RMM tools for interactive access. During the session they run PowerShell to silently install a malicious MSI that stages a portable Node.js runtime and obfuscated JavaScript implant for C2, executing follow-on payloads via rundll32. Operators then perform host and Active Directory reconnaissance, capture desktop screenshots, and pivot via WinRM on port 5985 to domain controllers and certificate authorities. The hands-on-keyboard chain, which can precede data theft and ransomware, blends into normal operations by relying on Teams, Quick Assist, msiexec, and Node.js; Microsoft shares hunting and mitigation guidance.

Microsoft Security Blog · 13d agoThreat actor in the wild

Infostealers Target Claude, Cursor, Codex and Other AI Agents to Steal Credentials and Sensitive Data

Gen Digital researchers report infostealer families Amatera, Remus and CallbackBeaver now harvest Claude, Cursor and Codex agent data, including tokens and MCP configs.

Gen Digital researchers found commodity infostealers extending their collection rules to local AI coding agent data from Claude, Cursor, Codex, Cline, Continue and OpenCode on Windows and macOS. Amatera targets Cline and Continue, Remus targets Claude, Cursor and OpenCode, and CallbackBeaver added Claude and Cursor with more than 5,000 samples observed in 30 days; Djinn Stealer hits Claude, Codex, Gemini, Cline, OpenCode and Kilo on macOS. Stolen data includes access and refresh tokens, prompt histories, conversation databases and MCP configurations holding API keys, potentially exposing connected source-control, cloud and ticketing systems. Remus is assessed as a Lumma Stealer variant using EtherHiding C2 resolution via Ethereum smart contracts.

GBHackers · 7d agoMalware in the wild1

ASCII smuggling isn't just an AI security risk

Microsoft tracked a phishing campaign peaking at 2.37 million daily messages that hid financial-lure keywords with invisible Unicode tag characters to evade filters.

Microsoft researchers uncovered a large phishing campaign that inserted invisible Unicode tag characters (e.g., U+E0020) inside common financial keywords like 'funding', splitting words so keyword, signature, and regex matches fail. The campaign peaked at more than 2.37 million messages in late February 2026, ran from about 150 finance-themed sender domains on a strict weekday-only schedule, and gradually declined to under 20% of peak weekday volume by late March, with residual spikes through mid-June. The technique repurposes ASCII smuggling, normally used for indirect prompt injection against AI assistants, for traditional email phishing evasion. Microsoft advises defenders to strip or fold invisible Unicode code points before content matching and to watch for bulk weekday spikes from churning finance-themed domains.

The Register · Security · 11d agoPhishing & fraud in the wild1

WordPress Plugins Compromised Without a Single File Change

Attackers poisoned bdThemes' JSON API feed to backdoor WordPress sites by serving malicious remote code without modifying plugin files.

Infosecurity Magazine reports a supply chain attack in which attackers poisoned a JSON feed used by bdThemes WordPress plugins. The compromised feed delivered malicious code that backdoored sites without changing any plugin files, evading file-integrity based detection. WordPress sites running the vendor's plugins were affected.

Infosecurity Magazine · Aug 10, 2026Malware in the wild

Trends in Web Threats: Old Web Skimmer Still Active Today

Unit 42 detected 577,000 landing URL incidents in Q1 2022, with an old web skimmer family still actively stealing payment card data.

Palo Alto Unit 42 detected 577,275 landing URL incidents (116,643 unique) and 2,043,862 malicious host URL incidents (180,370 unique) between January and March 2022. Web threat volumes declined after the November 2021 holiday peak, but an old web skimmer family remained active. Business and economy sites overtook personal sites as the most common apparently benign entry points. Most malicious domains geolocated to the United States, Germany, and Russia, though proxy servers and VPNs obscure true locations.

Palo Alto Unit 42 · Aug 17, 2026Research

Researcher shows how Claude Code can be tricked simply by asking it to summarize a website

Researcher wunderwuzzi showed Claude Code can be hijacked via prompt injection simply by asking it to summarize a website.

Security researcher Johann Rehberger (wunderwuzzi) demonstrated that Claude Code can be manipulated through prompt injection by simply asking it to summarize a website. Instructions embedded in fetched web content are executed by the agent, hijacking its behavior. The Register frames the finding as another demonstration of prompt injection risks in agentic coding tools that ingest untrusted web content.

The Register · Security · 18d agoAI safety & security1

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

CiteShade: Citation Laundering in Multi-Source Retrieval-Augmented Generation and Its Counterfactual Defense

CiteShade attack makes RAG models cite trusted sources for attacker-chosen wrong answers, raising wrong-answer rate from 0.01 to 0.68.

CiteShade is presented as the first citation laundering attack against multi-source retrieval-augmented generation: an attacker controlling a single source induces a wrong answer falsely attributed to a trusted source, even while correct evidence remains in context. The attack is formalized via three necessary conditions (retrieval, generation, citation) constructible without any instructions, raising wrong-answer rate from 0.01 to 0.68 on multi-hop QA, with source deletion confirming the malicious source as causal driver. Vulnerability tracks a model's citation propensity rather than scale, reaching CLR 0.84 with explicit instruction and 0.64 without on the most citation-prone model. Perplexity filtering and citation-support checking prove insufficient; the authors propose a counterfactual defense verifying which source actually drove the answer.

arXiv cs.CR · 2d agoAI safety & security1

Recent Trends in Internet Threats: Common Industries Impersonated in Phishing Attacks, Web Skimmer Analysis and More

Unit 42 analyzed 67 million malicious URLs and domains in H2 2022, a 52% increase, highlighting phishing impersonation and web skimmer trends.

Unit 42 observed more than 67 million unique malicious URLs, domains and IPs between July and December 2022, a 52% increase over the first half of the year. Malicious JavaScript detections grew 99.3%, with over 4 million malicious JS samples hosted on 4.8 million URLs. Over 85% of hosting infrastructure was concentrated in eight countries, led by the United States, Brazil and China. The report also analyzes industries spoofed in phishing pages and includes a web skimmer case study on a Tranco top 1 million website.

Palo Alto Unit 42 · Aug 17, 2026Research

Breaking the Seal: Static Deobfuscation of JSCeal’s Compiled V8 Bytecode

Check Point's hasherezade details static deobfuscation of JSCeal, a V8-bytecode stealer targeting cryptocurrency applications since March 2024.

JSCeal is an infostealer distributed as compiled V8 bytecode (.jsc) executed by a bundled Node.js runtime, aimed at cryptocurrency applications. Other vendors track the same family under the names WEEVILPROXY or MeadowLocust. Check Point Research has tracked the campaign since early 2024, with activity dating back to March 2024. The write-up presents a static approach to unpacking the bytecode without executing it.

Check Point Research · 16d agoMalware in the wild1

Suspected China-Nexus Actor Exploits VMware vCenter Flaw, Deploys Babuk

QUIRSO attributes exploitation of VMware vCenter CVE-2026-59310 to a suspected China-nexus actor that hit 361 IPs in 47 countries, deploying backdoors and Babuk.

German incident response firm QUIRSOS assessed with moderate confidence that a suspected China-nexus actor, likely operating in UTC+08:00 hours, exploited VMware vCenter flaw CVE-2026-59310 (CVSS 9.8 directory traversal) beginning five days after Broadcom's July 29 patch. The campaign compromised 361 unique victim IPs across 47 countries, most in Germany, the US, Turkey, Iran, and France. The actor abused cron jobs, a XOR-obfuscated 'linuxFile' WebSocket backdoor with systemd/cron persistence, a JSP web shell, SSH authorized-keys manipulation, and a reverse SSH tool, with one Babuk deployment reported. A separate vCenter 'vcenter_admin' account creation consistent with CVE-2026-59309 exploitation was also observed from August 1.

The Hacker News · Aug 17, 2026Threat actor in the wildCVE-2026-59310CVE-2026-593091

InceptionRAG: Stealthy Poisoning Attack Against Retrieval-Augmented Generation

InceptionRAG fragments malicious payloads into dormant passages that trigger LLMs to self-deduce misinformation via multi-hop reasoning, bypassing existing RAG poisoning defenses.

Researchers introduce InceptionRAG, a stealthy corpus poisoning attack against retrieval-augmented generation that splits a malicious payload into a chain of individually harmless dormant passages. When retrieved together, the passages induce LLMs to self-deduce target misinformation through multi-hop reasoning, achieving over 80% attack success rate across three datasets and three LLMs under rigorous adversarial constraints. A zeroth-order suffix optimization (ZOSO) method automates authoritative suffix generation in black-box settings. The authors also propose HODOR, a document isolation defense that decouples adversarial logical dependencies.

arXiv cs.CR · 1d agoResearch

Hackers Use Fake Claude and ChatGPT Installers to Infect Mac Users With Password-Stealing Malware

Attackers distribute MacSync macOS infostealer via fake Claude and ChatGPT installers and sponsored search ads, stealing passwords, cookies, keys, and wallets.

SEQRITE reports a malware-as-a-service campaign pushing MacSync, a macOS password stealer, through sponsored search results and fake Claude and ChatGPT download pages. ClickFix-style prompts trick users into pasting a Terminal command that launches a stager, which loads an in-memory AppleScript to harvest credentials. The malware collects browser vaults, Keychain data, SSH keys, session cookies, messaging sessions, and cryptocurrency wallets, then persists via renamed LaunchAgents and can request screen-recording permissions.

Cyber Security News · 6d agoMalware in the wild 2 sources

ANY.RUN & SentinelOne: One Workspace, Instant Context for Rapid Response

ANY.RUN integrates its interactive sandbox, IOC lookups, and STIX/TAXII threat feeds natively into SentinelOne for faster automated malware triage.

ANY.RUN and SentinelOne launched connectors that embed interactive sandbox analysis and threat intelligence into the SentinelOne console via Singularity Hyperautomation. Suspicious files and URLs from alerts are automatically submitted to the ANY.RUN sandbox, with behavioral verdicts and risk scores returned into alert notes. On-demand IOC lookups draw on sandbox history from 16,000 organizations and 700,000 analysts. A separate STIX/TAXII feed streams verified malicious IPs, domains, and URLs through the SentinelOne Marketplace TAXII Connect app.

ANY.RUN · 10h agoTools

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 · 23d agoThreat actor

VU#308749: Remote Code Execution and Arbitrary File Read Vulnerabilities in Kaltura Servers

Insecure deserialization in Kaltura's legacy HTML5 Player V2 (mwEmbed) allows arbitrary file read and remote code execution; Player V7 is unaffected.

CERT/CC issued VU#308749 for two flaws in Kaltura's HTML5 Player V2 library (mwEmbed/html5lib), both caused by the same insecure deserialization bug. The flaws enable arbitrary file read and remote code execution via the exposed mwEmbedLoader.php endpoint. Affected versions include html5lib v2.45, v2.103 and earlier, and other v2.x releases; the currently supported Player V7 is unaffected. No evidence of exploitation was cited.

CERT/CC Vulnerability Notes · 22d agoVulnerability

Phishing Campaign Sends Millions of Emails Using Invisible Unicode to Evade Filters

Microsoft warns of a high-volume phishing campaign using invisible Unicode characters to split keywords like 'funding' and evade filters, peaking at 2.37 million daily messages.

Microsoft's Security Research team documented a high-volume phishing operation inserting deprecated Unicode Tags characters (U+E0000-U+E007F) inside financial keywords such as 'funding' so literal-string and regex email filters stop matching them. The campaign ran on a weekly cadence with 1-2.37 million weekday messages between February and May 15, 2026, peaking on February 26, 2026. It used hundreds of disposable finance-themed sender domains and relayed mail through ActiveCampaign's click-tracking infrastructure (acemlnd[.]com, activehosted[.]com), lending legitimate platform reputation. Microsoft ties the activity to an AI-assisted SBA loan phishing campaign that Fortra's FIRE team disclosed in September 2025.

The Hacker News · 12d agoPhishing & fraud in the wild

Subgroup Membership Inference Audits of Differentially Private Synthetic Text

Audits of 32 differentially private synthetic-text releases show subgroup membership leakage is concentrated in few records and systematically underestimated by average-case attacks.

The paper defines a subgroup-targeted membership inference game in which the target pool is an explicit parameter, to audit residual leakage in differentially private synthetic text releases. The audit instantiates 32 proxies across four datasets, three generators (DP-SGD fine-tuning, API-based prompting, and activation steering), and five privacy budgets. DP substantially reduces average leakage at every budget, but remaining leakage is concentrated: roughly a tenth of records carries about 40% of it, and the noise removes more measured leakage from random records than from high-risk ones. Which records leak depends on the release mechanism, so record-level risk cannot be assessed independently of the release.

arXiv cs.CR · 7d agoResearch

Ransom Busters Claims It Hacked Ransomware Servers, Asks Victims for Up to $60,000

GuidePoint reports a ransomware affiliate posing as 'Ransom Busters' charges victims $20,000-$60,000 to delete stolen data, and details UNC6671's $8M AitM extortion wave.

GuidePoint's GRIT team reports that 'Ransom Busters', likely a ransomware affiliate active across multiple RaaS operations including DragonForce, Settra and Anubis, proactively emails victims claiming it deleted their stolen data and backups for a $20,000-$60,000 fee, citing claimed access to RaaS administrative panels for over three years. Two analyzed intrusions shared tooling: SoftPerfect Network Scanner for reconnaissance, s5cmd-based exfiltration to AWS cloud storage, an RMM tool installed via PowerShell, a backdoor account with password 'Numlock!123' and the same attacker hostname DESKTOP-BBETH6K. Separately, GRIT detailed UNC6671's (Cordial Spider) adversary-in-the-middle vishing operation running since April under five extortion brands, with more than $8 million across 15 Bitcoin wallets, an average of $600,000 per payment, and 78 phishing sub-domains across 76 organizations, 40% in financial services.

The Hacker News · 28d agoThreat actor in the wild1

Robust Coverless Linguistic Steganography via Sentence Embedding Space with Global Resynchronization

Researchers propose a coverless steganographic framework encoding messages as hierarchical clustering paths in sentence embedding space with a Global Resynchronization Mechanism for robustness.

An arXiv paper proposes encoding secret messages as hierarchical clustering paths in the sentence embedding space rather than token space, improving decoding stability against word- and sentence-level textual perturbations. A Global Resynchronization Mechanism (GRM) reframes variable-length bitstreams as discrete symbols anchored to semantic subspaces to prevent bit-slippage. Experiments show substantial robustness improvements while maintaining embedding capacity and resistance to statistical analysis.

arXiv cs.CR · 12d agoResearch

FBI takes down China-linked hacking network behind attacks on NASA, DOJ and U.S. Senate

FBI seized domains disabling QScan and QTRouter malware run by China-linked QTFY group behind intrusions at NASA, DOJ, Senate and other agencies.

The Justice Department and FBI seized domains hard-coded into two malware tools, QScan and QTRouter, operated by a Chinese state-sponsored group called QTFY, tied to a Nanjing-based company that sold hacking services to China's Ministry of State Security and the PLA. QScan infected IoT devices worldwide while QTRouter combined them with commercial proxies and rented servers to build an obfuscation network that masked attack origins. Victims include NASA, the Federal Reserve, the Departments of Energy and Justice, HHS, NIH, and the U.S. Senate. The FBI and NSA published a joint advisory with indicators of compromise, the latest in operations against Mustang Panda, Flax Typhoon, and Volt Typhoon infrastructure.

Help Net Security · 20d agoThreat actor in the wild