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6 stories in the last 30d

JSCeal Hides Crypto Malware in V8 Bytecode

Check Point details JSCeal, a crypto-stealing malware delivered as compiled V8 bytecode, and built a decompiler pipeline to expose its capabilities.

JSCeal, tracked by Check Point Research since early 2025, is a cryptocurrency stealer delivered as heavily obfuscated JavaScript compiled to V8 bytecode (.jsc) and run by a bundled Node.js runtime. Check Point, presenting at Black Hat USA 2026, extended the open-source View8 decompiler into a pipeline that recovered readable code from 23 samples, revealing theft of browser credentials and cookies, Telegram sessions, keystrokes, screenshots, HTTPS traffic interception with attacker-controlled certificates, and automated Google account takeover. Targeted overrides rewrite content for Binance, Bybit, and Ledger users. Later samples added AES-256-CBC encryption with externally supplied keys and expanded targeting to macOS.

Security Affairs · 9d agoMalware1

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

New SLEEPWALKER Backdoor Waits for One Crafted Packet, Then Runs Its Own Bytecode

A new Windows backdoor dubbed SLEEPWALKER hides as ESET Management Agent's dpapi.dll, waits for a crafted network packet, then executes custom 23-instruction bytecode.

Researcher Dominik Reichel documented SLEEPWALKER, an unsigned 59,904-byte 64-bit Windows DLL that side-loads into ESET Management Agent's ERAAgent.exe while impersonating dpapi.dll. The implant monitors every network interface indefinitely for a specifically crafted trigger packet, then executes commands written in a custom 23-instruction bytecode language over six transports, including TCP, UDP, ICMP, SMB named pipes, raw promiscuous capture, and VMware VMCI. It has no embedded infrastructure, makes no outbound connections of its own, and requires prior local administrator access to install; no victims, attribution, or in-the-wild deployment are confirmed. Reichel assesses the design as consistent with a targeted, well-resourced operation, while ESET calls the scenario's security relevance negligible since it provides no new access path.

The Hacker News · 12d agoMalware1

Nearly 1 in 10 Exposed LiteLLM Gateways Accepted the Example "sk-1234" Admin Key

Wiz found 294 of 3,074 internet-facing LiteLLM gateways accepted the documented default admin key sk-1234, exposing provider API keys and cloud IAM credentials.

Wiz Research's February Shodan scan found 3,074 LiteLLM gateways, 294 of which accepted the setup guide's sk-1234 admin key; 191 had no master key set and would accept any credential. The master key doubles as the authentication switch, and before 1.82.0-stable a gateway started without one granted every request full admin rights, exposing stored provider API keys, prompts, and MCP-connected tools. A documented pass-through endpoint lacks checks against private and cloud metadata addresses, letting an admin-key holder retrieve cloud IAM credentials, though no real-world abuse is reported. Related LiteLLM flaws include CVE-2026-59821 (disputed guardrail code execution), CVE-2026-59822 (CVSS 8.8, added to CISA KEV on September 2 and observed against Wiz honeypots), and CVE-2026-42271, used to install a cryptominer.

The Hacker Newsupdated · 6d agofirst · 6d agoVulnerability in the wild 3 sourcesCVE-2026-59821CVE-2026-59822CVE-2026-42271+2 CVEs

JSCeal Malware Can Bypass Google Authentication Using Stolen Session Cookies

Check Point details JSCeal, a V8-compiled JavaScript stealer that replays stolen cookies to bypass Google authentication, spread via crypto malvertising.

Check Point Research's new report analyzes JSCeal, a compiled V8 JavaScript malware obfuscated with javascript-obfuscator using RC4-protected strings, control-flow flattening, and proxy functions. Delivered through fake TradingView installers on malvertising sites overlapping the WEEVILPROXY/MeadowLocust and SourTrade campaigns, it harvests cookies, passwords and OAuth tokens from Chromium browsers, records keystrokes and screenshots, and can replay stolen Google session cookies to bypass authentication. It also installs a local proxy with service-specific handlers for Binance, Bybit, and Ledger to intercept and modify cryptocurrency-related traffic.

The Hacker News · 9d agoMalware in the wild1

Cybercriminals Turn GTA VI Leaks Into Malware Bait

Attackers spread fake 113GB GTA VI builds whose 50KB payload whitelists the entire C: drive in Windows Defender, alongside credential phishing and infostealer campaigns.

Researchers found that a 113GB file claiming to be a playable Grand Theft Auto VI build is 99.99% empty data hiding a tiny malicious payload that excludes the entire C:\ drive from Windows Defender and kills security software, preparing systems for follow-on attacks. Related lures include fake GTA 6 Windows installers using DLL side-loading, a fake 'GTA 6 Mobile' app redirecting to infostealer and ransomware infrastructure, and counterfeit Rockstar Social Club login pages harvesting credentials. The fakes ride genuine leak momentum from the leaker CyberLeek, and Kaspersky separately documented over 19 million attempted downloads of game-themed malware in a year, with GTA, Minecraft, and Call of Duty the most abused brands. No legitimate playable GTA VI build is circulating; the game launches November 19 on consoles.

Security Affairs · 23d agoMalware in the wild