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7 stories in the last 7d

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DomainAllCyberAIWindow24h3d7d30dAllIn the wildImportant onlyShow duplicates
CategoryAllVulnerability 6Malware 3Research 3Model release 2Threat actor 2AI tools & infra 1AI safety & security 1Phishing & fraud 1
SeverityAllcritical 0high 4medium 7low 3info 5

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

Apple Xcode Integer Underflow Flaw Lets Crafted Archives Leak Memory and Crash Builds

Researchers disclosed an integer underflow in Apple's Mach-O archive parser that lets crafted static libraries crash Xcode builds or leak process memory.

SecureLayer7 disclosed an integer underflow in the mach_o::Archive::Entry::name() function in Apple's open-source dyld project, reported to Apple Product Security on May 23, 2026, with no public patch after more than 90 days. Crafted static archives (.a files) cause the parser's unsigned index to wrap to SIZE_MAX, producing SIGSEGV crashes in the ld-prime linker, out-of-bounds reads that may print adjacent memory to stderr, or SIGABRT in libtool and ranlib. The modern parser is used by ld-prime, the default linker for arm64, arm64e, and x86_64 since Xcode 15, while legacy ld-classic is unaffected. Crafted archives need only be processed, creating supply-chain risk via vendored SDKs, binary dependencies, and CI pipelines.

GBHackers · 6d agoVulnerability1

Homebrew 7.0.0 is out, here’s what changed for security

Homebrew 7.0.0 closes eight security advisories, including a High sudo execution bug fixed in 6.0.12, and ships brew vulns vulnerability scanning.

Homebrew 7.0.0 closes eight security advisories rated one High, two Moderate, and five Low. The High flaw let unsigned cask removal metadata execute commands with sudo (fixed in 6.0.12), while the 7.0.0 Moderate closes a LaunchServices escape that let a malicious cask execute code outside the macOS install sandbox. The release ships brew vulns, which checks installed formulae against OSV.dev, extends build attestation verification to third-party tap bottles, and replaces Bubblewrap with Landlock sandboxing on Linux.

Help Net Security · 1d agoVulnerability

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 · 5d agoThreat actor in the wild 3 sources1

SloppyRAT: A New Tool For Ransomware Attacks

Zscaler details SloppyRAT, a new DLL backdoor delivered via ClickFix lures that stages CastleLoader and CastleRAT ahead of ransomware attacks.

Zscaler ThreatLabz analyzed SloppyRAT, a DLL-based backdoor distributed via ClickFix lures that abuses finger.exe over TCP port 79 to download a batch script. The malware copies curl.exe to download IronPython 3.4.2 from GitHub and executes zlib-compressed Base64-encoded Python to deploy CastleLoader and CastleRAT, then reflectively loads SloppyRAT in memory. It hinders analysis using XOR stack-string obfuscation, a modified affine cipher with modulus 127, and 13 runtime-decrypted code blocks, while communicating with C2 over a reverse SOCKS channel.

Zscaler ThreatLabzupdated · 5d agofirst · 6d agoMalware in the wild 3 sources

Smishing Hackers Can Watch Every Keystroke as Victims Enter Card Details and OTPs

Group-IB details the JWR smishing kit, used by the Outsider cluster, that streams keystrokes and OTPs to fraudsters in real time via WebSocket.

Group-IB linked the JWR phishing kit to an operator cluster it tracks as Outsider within the broader Smishing Triad ecosystem. Fake toll, parcel, and delivery messages lead to live phishing pages that capture card numbers, passwords, and one-time passcodes before victims submit forms. The kit supports up to 32 guided pages, AES-256-CTR wrapped traffic with keys embedded per message, rotating short links and domains, and WordPress or Shopify integration markers, enabling account takeover and unauthorized payments.

Cyber Security News · 8h agoPhishing & fraud in the wild 2 sources

Casbaneiro Banking Trojan Uses Distributed C2 Servers to Evade Detection and Target Bank Users

Casbaneiro banking Trojan targets Latin American bank users via phishing PDFs, geofencing, AutoIt staging, and distributed C2 servers to evade detection.

FortiGuard Labs detailed a Casbaneiro banking Trojan campaign observed in August 2026 targeting users in Argentina, Peru, Colombia, and Mexico via fake invoice and legal-notice emails. The operation uses geofenced landing pages, an HTA downloader with WMI-based sandbox checks, a legitimate AutoIt interpreter, and process injection into RegSvcs.exe (fallback mobsync.exe). C2 activation is conditional on victims visiting banking websites, enabling keyboard control, clipboard manipulation, and fake overlay windows for bank-focused fraud, while distributed exfiltration servers and unusual HTTP 403-based signaling hinder analyst correlation.

GBHackers · 2d agoMalware in the wild1