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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

Attackers are weaponizing the gap between Chromium fixes and Chrome patches

Espionage actors use the BlueMoon exploit kit to chain Chrome V8 and Windows kernel zero-days via spear phishing, gaining full admin on unpatched endpoints.

Proofpoint, working with Google Threat Intelligence Group, Microsoft Threat Intelligence Center and Volexity, reports that the BlueMoon exploit kit chains V8 type confusion CVE-2026-85046, V8 sandbox escape CVE-2026-87491 and Windows kernel LPE CVE-2026-85880, all rated high severity. The V8 flaws were fixed in upstream Chromium source but had not yet reached Chrome stable releases, creating a patch gap that attackers reverse-engineered and weaponized. A China-aligned state-sponsored actor used the kit from August 28 against a small number of US NGOs, mining and commodity trading firms via rapport-building spear phishing, and within days several mostly China-linked espionage clusters adopted BlueMoon. The chain yields full Windows admin privileges from a single phishing click; defenders should patch Chrome and Windows, apply Proofpoint detections and hunt for leftover artifacts.

CSO Onlineupdated · 29m agofirst · 5d agoExploit / PoC in the wild 19 sourcesCVE-2026-85046CVE-2026-87491CVE-2026-85880

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

Chrome V8 Zero-Day Exploited in the Wild Enables Code Execution Inside Sandbox

Google patches actively exploited Chrome V8 zero-day CVE-2026-87491, an out-of-bounds write enabling sandboxed code execution via crafted HTML pages.

Google released Chrome 153.0.8010.36/.37 fixing 230 vulnerabilities, including CVE-2026-87491, an out-of-bounds write in the V8 engine that allowed remote code execution inside the sandbox via a crafted HTML page and is confirmed to be exploited in the wild. The flaw was reported on August 6, 2026 by Jihyeon Jeong of Compsec Lab, Seoul National University, who received a $2,500 bug bounty. This is the seventh actively exploited Chrome zero-day of 2026. The update also fixes five critical flaws in WebGL and Cast, plus a high WebPackaging use-after-free (CVE-2026-87639) credited to OpenAI Codex Security.

The Hacker News · 7d agoExploit / PoC in the wildCVE-2026-87491CVE-2026-2441CVE-2026-3909+10 CVEs

LACE: Layer-Wise Compression for Dynamic Frame Rate Codecs

LACE introduces layer-wise compression for dynamic frame rate audio codecs, cutting sequence lengths and speeding TTS inference while preserving quality.

LACE (Layer-Adaptive Codec Encoding) applies an independent compression step at each quantization layer of a neural audio codec, enabling layer-specific segmentation boundaries instead of shared ones. Union alignment and boundary anchor mechanisms keep durations consistent for downstream text-to-speech. On LibriTTS, LACE achieves a better rate-quality tradeoff than prior dynamic frame rate codecs and improves TTS inference efficiency at competitive synthesis quality. Code is released in the ESPnet3 codec recipe.

arXiv cs.AI / cs.LG / cs.CL · 23h agoAI research1

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

Retrofitting Code Using LLMs to Support Exceptional Behavior

EXCODER combines static/dynamic analysis with LLMs to retrofit exception-handling code, achieving 85.92% pass@1 with Qwen 2.5 Coder 32B on Java benchmarks.

The paper introduces the task of retrofitting existing code with Exception Related Code (throw statements, guarding conditions, try/catch blocks) so that given Exceptional Behavior Tests pass. EXCODER performs context engineering by integrating static and dynamic program analysis output with LLMs; it was evaluated on a benchmark built from 304 methods across 75 GitHub Java projects. Combined with Qwen 2.5 Coder 32B, EXCODER achieves pass@1, 5, and 10 rates of 85.92%, 86.18%, and 86.51%, roughly 13 percentage points over baseline, and manual inspection reveals remaining limitations.

arXiv cs.AI / cs.LG / cs.CL · 7d agoAI research1

I tested 10 model/harness combinations on the same Three.js task

A developer benchmarked 10 model/harness combinations on a Three.js task; Qwen 3.8 27B on OpenCode scored 95.64% fastest at 8m48s.

The author ran an identical Three.js sci-fi hangar build prompt across 10 model/harness combinations and recorded score, tokens, durations, and tool errors. Qwen 3.8 27B x-high on OpenCode achieved 95.64% in 8m48s, the best fast result, while GLM 5.3 Flash Max on OpenCode scored highest at 96.89% in 20m28s. Other runs included GLM 5.3 Flash, Luna 5.6, SOL 5.6, and Astra 6.0 across Codex Open, OMP Open, OpenCode, DSH, and PTC harnesses, with scores ranging from 78.54% to 96.89%.

Towards Scalable and Cost-Efficient Vulnerability Detection: A Study on Automatic Query Generation

A study finds LLM-synthesized CodeQL queries improve average F1-score by 82% over baseline queries, offering scalable vulnerability detection versus direct LLM scanning.

Researchers conducted an empirical study evaluating whether LLMs can synthesize executable CodeQL queries from National Vulnerability Database vulnerability data. LLM-generated queries significantly enhanced baseline CodeQL suites, yielding an 82% improvement in average F1-score across a diverse set of real-world vulnerabilities. A cost-benefit analysis shows direct LLM-based scanning of entire repositories is often computationally and financially prohibitive, while LLM query synthesis offers a scalable and cost-effective alternative for large-scale vulnerability detection.

arXiv cs.CR · 7d agoResearch1

CVE-2026-70469: Apache NiFi: Improper Handling of Case Sensitivity for Content-Encoding in HTTP Requests

Apache NiFi CVE-2026-70469: duplicate or non-standard Content-Encoding headers bypass gzip request filtering in NiFi 2.11.0's REST API.

Apache NiFi disclosed CVE-2026-70469, rated High, affecting the Jetty-based REST API module (org.apache.nifi:nifi-jetty) in version 2.11.0. NiFi 2.11.0 disabled gzip-encoded HTTP requests and rejects those carrying the standard Content-Encoding header, but the framework enforcement filter fails to check multiple instances of the header and does not reject non-standard gzip identifiers, allowing crafted requests to evade the check. The disclosure was posted to oss-security by David Handermann.

CISA KEV: Google Chromium V8 Type Confusion Vulnerability — Google Chromium V8 (CVE-2026-85046)

CISA added actively exploited Chromium V8 type confusion CVE-2026-85046 to the KEV catalog, requiring federal mitigation by September 18.

CISA added CVE-2026-85046, a type confusion vulnerability in Google Chromium's V8 JavaScript engine, to the Known Exploited Vulnerabilities catalog. The flaw allows a remote attacker to execute arbitrary code inside the browser sandbox via a crafted HTML page and affects Chromium-based browsers including Google Chrome, Microsoft Edge, and Opera. Federal agencies must apply vendor mitigations by 2026-09-18 under BOD 26-04; CISA notes known ransomware campaign use is currently unknown.

ZDI-26-588: Fabric.js loadFromJSON Server-Side Request Forgery Vulnerability

ZDI disclosed a server-side request forgery in Fabric.js loadFromJSON (CVE-2026-19504) that can leak sensitive information from affected implementations.

Zero Day Initiative advisory ZDI-26-588 describes a server-side request forgery vulnerability in the Fabric.js canvas library's loadFromJSON function. Exploitation requires interaction with the library and attack vectors vary by implementation, potentially exposing sensitive information. The issue is rated 4.0 on the CVSS scale and tracked as CVE-2026-19504. The advisory does not report exploitation in the wild.

Google Releases Chrome Update to Patch Actively Exploited V8 Zero-Day

Google patches actively exploited Chrome V8 zero-day CVE-2026-85046 (CVSS 8.8); CISA adds it to KEV with a September 18 deadline.

Google fixed 12 Chrome vulnerabilities, including CVE-2026-85046, a high-severity (CVSS 8.8) type confusion bug in the V8 JavaScript and WebAssembly engine. The flaw, reported by researcher Salvatore Gulizia on August 4, 2026, allows remote arbitrary code execution inside the browser sandbox via a crafted HTML page. Google confirmed the exploit exists in the wild, and CISA added the CVE to its KEV catalog, requiring Federal Civilian Executive Branch agencies to patch by September 18, 2026. This is the sixth actively exploited Chrome zero-day patched in 2026.

The Hacker News · 12d agoExploit / PoC in the wildCVE-2026-85046CVE-2026-2441CVE-2026-3909+3 CVEs1

CISA Warns of Chromium Type Confusion 0-Day Vulnerability Actively Exploited in Attacks

CISA added the actively exploited Chromium V8 type confusion zero-day CVE-2026-85046 to its KEV catalog, urging patching of Chrome, Edge, and Opera.

CISA added CVE-2026-85046, a V8 type confusion flaw (CWE-843) in Chromium-based browsers, to its Known Exploited Vulnerabilities catalog. A remote attacker can trigger arbitrary code execution inside the browser sandbox via a specially crafted HTML page. Google Chrome is directly affected, and Microsoft Edge, Opera, and other Chromium-based browsers may also be impacted depending on their V8 version. Google has released a Stable channel Chrome update, and CISA directs mitigations under Binding Operational Directive 26-04.

Cyber Security News · 8d agoExploit / PoC in the wildCVE-2026-85046

Video compressor

Simon Willison built a browser-based video compressor using the WebAssembly FFmpeg build, generated by Claude Fable 5.1 in Claude Code for web.

Willison recorded a demo video of his Equal Earth animation and wanted an optimized web-publishable version. He had Claude Fable 5.1 running in Claude Code for web build a compressor around the WebAssembly port of FFmpeg. The post is a short vibe-coding demonstration, not a model release or security event.

Simon Willison · 8d agoAI tools & infra

Google fixes the sixth actively exploited Chrome zero

Google patched 12 Chrome flaws including actively exploited V8 type confusion zero-day CVE-2026-85046 (CVSS 8.8), enabling sandboxed remote code execution via crafted webpages.

Google released Chrome Stable 152.0.7977.82/.83 for Windows and Mac and 152.0.7977.82 for Linux, fixing 12 vulnerabilities including CVE-2026-85046, a type confusion in V8 with a CVSS score of 8.8. Google says an exploit exists in the wild, making this the sixth actively exploited Chrome zero-day of 2026. The bug affects the JavaScript and WebAssembly engine and allows arbitrary code execution inside the browser sandbox via a specially crafted HTML page. Researcher Salvatore Gulizia (Serotav) reported the flaw on August 4, 2026 and received a $1,000 bounty.

Security Affairs · 12d agoExploit / PoC in the wildCVE-2026-85046CVE-2026-2441CVE-2026-3909+3 CVEs1

TasmScan: Continuation-Aware Taint Analysis for TVM Bytecode with Savelist Abstraction

TasmScan introduces source-free taint analysis for TON smart-contract bytecode, detecting 95.3% of defects with 96.8% precision and 17x speedup.

TasmScan is the first bytecode-level static analysis framework for the TON Virtual Machine, enabling cross-continuation data flow reasoning without source code by modeling savelist semantics through forward register analysis with formal over-approximation guarantees. It lifts bytecode into a typed intermediate representation (TASIR) and performs path-sensitive taint analysis. On a 208-contract benchmark with human-confirmed ground truth it detects 95.3% of defects across five classes at 96.8% precision, and resolves 294,546 dynamic continuation targets with 100% precision across 2,921 registry contracts. It achieves a 17x median speedup over symbolic-execution baselines.

arXiv cs.CR · 1d agoResearch

MongoDB security advisory (AV26-911)

Canada's Cyber Centre warns MongoDB Java Driver and Laravel MongoDB (PHP) have vulnerabilities fixed in versions 5.11.1 and 5.11.0.

The Canadian Centre for Cyber Security (AV26-911) reports MongoDB vulnerabilities affecting the Java Driver prior to 5.11.1 and Laravel MongoDB (PHP) prior to 5.11.0. Fixed issues include a native heap use-after-free during cancellation racing a KMS credential fetch in reactive encryption (JAVA-6276) and a query builder fix forcing literal equality when 3-arg where clauses use '=' with array values (PHPLARA-260). Administrators are urged to review the advisories and apply the updates.

Canadian Centre for Cyber Security · 5d agoAdvisory1

Re: Vulnerabilities fixed in libxml2-2.15.4

libxml2 2.15.4 patches two flaws including a heap buffer overflow in xmlDictAddQString tracked as CVE-2026-86137 and CVE-2026-86138.

libxml2 releases before 2.15.4 are affected by an integer overflow in xmlDictAddQString in dict.c that leads to a heap-based buffer overflow, tracked as CVE-2026-86137 and CVE-2026-86138. The oss-security post from Debian's Salvatore Bonaccorso flags the fixed release for downstream tracking. No exploitation is mentioned in the disclosure.

VU#728712: Konami's Metal Gear Online 3 contains a heap-based buffer overflow

CERT/CC details CVE-2026-19874, a heap overflow in Metal Gear Online 3 letting match hosts execute code on lobby members' machines.

VU#728712 describes a heap-based buffer overflow in Konami's Metal Gear Online 3, tracked as CVE-2026-19874, affecting version 1.1.2.8 (Steam AppID 287700). The input-validation flaw lies in processing Steam lobby metadata tied to the player-removal feature, letting a match host trigger remote code execution on lobby members' machines via specially crafted data. The game is an 8v8 competitive shooter using Steam Matchmaking for lobbies.

Four Spy Groups Used the Same Chrome and Windows Exploit Kit Within a Week

Proofpoint links four espionage clusters, including China's APT31, using shared exploit kit BlueMoon chaining Chrome V8 and Windows ALPC zero-days.

Proofpoint reports a previously undocumented exploit kit, BlueMoon, chains Chrome V8 type confusion CVE-2026-85046 with an unassigned V8 sandbox escape and Windows ALPC heap overflow CVE-2026-85880 to achieve code execution and local privilege escalation. APT31 first used it on August 28, 2026 against US NGOs, mining, and commodity trading firms, deploying the GemStone browser backdoor disguised as a Google Gemini extension via the GhostChrome-X integrity bypass. UNK_LateNight, UNK_DoubleCheck, and UNK_QuietRacket followed on September 2-3, targeting US aerospace, Vietnamese manufacturing, and Indonesian/Singaporean sectors with ShadowPad and sideloaded Rust and .NET payloads. Both V8 flaws were patch-gap zero-days, and verbose code suggests possible AI-assisted development.

X-AuT: Progressive Audio-Encoder Compression for Speech LLMs with Cross-Scale Distillation

XPeng AI's X-AuT prunes speech LLM audio encoders, cutting Qwen3-ASR-0.6B error from 5.61% to 5.27% with fewer parameters.

X-AuT is a progressive compression framework for speech LLM audio encoders that selects layer combinations via short behavioral probes and restores pruned models using cross-scale distillation and LoRA finetuning while keeping the language-model backbone frozen. Compressing Qwen3-ASR-0.6B from 18 to 16 audio-encoder layers lowered macro-average error from 5.61% to 5.27% on ten Chinese-English benchmarks. A 14-layer model reached 5.75% error with 20.7% fewer audio-tower parameters, and progressive pruning outperformed direct pruning (5.75% vs 6.73%).

Hugging Face daily papers · 6d agoAI research

U.S. CISA adds Google Chromium V8 flaw to its Known Exploited Vulnerabilities catalog

CISA added actively exploited Chrome V8 type-confusion flaw CVE-2026-85046 (CVSS 8.8) to its KEV catalog; Google patched it in Chrome 152.

CISA added CVE-2026-85046 (CVSS 8.8), a V8 type confusion flaw, to its Known Exploited Vulnerabilities catalog, requiring US federal agencies to patch by September 18, 2026. Google fixed it in Chrome Stable 152.0.7977.82/.83 for Windows and Mac and 152.0.7977.82 for Linux, alongside 11 other vulnerabilities. The bug lets a remote attacker execute arbitrary code inside the browser sandbox via a crafted HTML page and is the sixth actively exploited Chrome zero-day of 2026. Researcher Salvatore Gulizia (Serotav) reported it on August 4, 2026.

Security Affairs · 11d agoExploit / PoC in the wildCVE-2026-85046CVE-2026-2441CVE-2026-3909+3 CVEs1

Diffs vs. Whole Files: An Empirical Comparison of Iterative Edit-Based and Direct Generation for Flutter/Dart Code Models

Empirical study finds direct whole-file generation beats iterative diff-based editing for Flutter/Dart code models on about 1,790 held-out tasks.

Researchers trained Rainbow-Pony-100M from scratch and fine-tuned Qwen2.5-Coder-0.5B in both direct-generation and diff-based regimes, then evaluated four resulting models on roughly 1,790 Flutter/Dart tasks. Direct generation outperformed diff-based generation on compilation pass rate, bits-per-byte, character-level similarity, and blinded LLM-judge ratings. Diff-based editing is competitive only on short, localized edits in refactoring and error-handling tasks, a property the authors call task locality.

Hugging Face daily papers · 11d agoAI research1

Molecular Déjà Vu: Digit-Level Retrieval of Published Values in Frontier Language Models

Audit of 22 frontier models finds widespread verbatim retrieval of published molecular property values, with higher reasoning increasing recall of memorized numbers.

An arXiv audit tests 22 frontier LLMs across 12 molecular regression benchmarks for verbatim retrieval of published values. More than 50% of the LLMs show verbatim retrieval on five datasets, and identical experiments are flagged 89% more often at a high reasoning level than at the lowest one. Suppressing retrieval moves model prediction errors closer together in relative terms, suggesting predictive capability is not determined solely by memorized values.

arXiv cs.AI / cs.LG / cs.CL · 12d agoAI research1

Flextype v1.0.0-alpha.3 CMS registerShortcodes() Remote Code Execution via Attacker-Controlled File Inclusion

Flextype CMS v1.0.0-alpha.3 allows PHP remote code execution via path traversal in the Entries API combined with shortcode file inclusion.

Flextype CMS v1.0.0-alpha.3 exposes a remote code execution path through the interaction of the Entries API and Shortcodes::registerShortcodes(). The /api/v1/entries endpoint accepts attacker-controlled entry identifiers containing path traversal sequences, allowing PHP-containing content to be written outside the intended entries directory. A subsequent attacker-controlled path can then be included and executed as PHP. Ron E posted the disclosure to the Full Disclosure mailing list on September 3, 2026.

Full Disclosure · 12d agoVulnerability 8 sources

Hackers Chain Chrome and Windows Zero-Days in New BlueMoon Exploit Kit Attacks

Multiple espionage actors, mostly China-nexus, are chaining Chrome V8 and Windows kernel zero-days (CVE-2026-85046, CVE-2026-85880) via the BlueMoon exploit kit against government and defense targets.

Proofpoint identified a new exploit kit dubbed BlueMoon chaining a Chromium V8 type-confusion RCE (CVE-2026-85046), a V8 sandbox escape, and a Windows kernel LPE (CVE-2026-85880). At least four distinct threat clusters, most with suspected China nexus, adopted the kit within days starting with TA412 (Violet Typhoon/APT31) on August 28, 2026. Both Chrome-side flaws were patch-gap zero-days with roughly a four-week exploitation window; the Windows LPE only works on Windows 10 and Server 2019/2022. TA412 used spearphishing posing as university interns to deliver the GemStone browser backdoor disguised as a Google Gemini extension; other clusters delivered ShadowPad via DLL sideloading and a Rust loader against targets in aerospace, government, and finance.

Cyber Security News · 7d agoExploit / PoC in the wildCVE-2026-85046CVE-2026-858801

CVE-2026-73334: Apache Parquet Hadoop: File-controlled KMS URL is forwarded to pluggable KmsClient that skips host validation

Apache Parquet Hadoop CVE-2026-73334: a file-controlled KMS URL reaches pluggable KmsClients without host validation in parquet-java 1.12 through 1.18.0.

Apache disclosed CVE-2026-73334, a moderate issue in the org.apache.parquet.crypto.keytools package of parquet-java, versions 1.12 through 1.18.0. The package implements envelope encryption that wraps data keys via a Key Management Service. A KMS URL controlled by the Parquet file is forwarded to a pluggable KmsClient that skips host validation, which could allow crafted files to redirect KMS requests.

oss-security · 8d agoVulnerabilityCVE-2026-733341

AutoTrans: AI-Assisted Automatic Translation of Security Assertions for RISC-V Processors

AutoTrans uses LLMs with regex extraction and formal verification to automatically translate security assertions across RISC-V processors, achieving 78% unattended acceptance.

AutoTrans is an automated framework for translating verified security assertions between RISC-V processor targets, where manual translation takes hours per assertion. It combines a regex-based SystemVerilog signal extractor to prevent LLM signal hallucination, a pinned prompt template yielding byte-identical prompts resilient to model updates, and JasperGold FPV formal verification of generated assertions. Applied with DeepSeek V4 to translate assertions between RISC-V targets such as IBEX and NS31A, it achieves a 78% automatic translation acceptance rate without human intervention and 100% after human refinement.

arXiv cs.CR · 7d agoResearch