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6 stories in the last 30d

Isolated-vm Flaw Lets Sandboxed JavaScript Escape to Host for Potential RCE

Critical type-confusion flaw in isolated-vm Node.js sandbox (GHSA-864f-rcv7-6rh4) enables guest-to-host escape and potential RCE; fixed in 6.2.0 and 7.0.1.

Endor Labs researcher Cristian-Alexandru Staicu found a type confusion in the ExternalCopy component's handling of the transferList option in isolated-vm, letting sandboxed JavaScript corrupt host-process memory and escalate from controlled-address crashes to full control-flow hijack of the host, i.e., potential remote code execution. The flaw, tracked as GHSA-864f-rcv7-6rh4 with no CVE yet, affects all versions through 7.0.0 of the library, which sees nearly 1 million npm downloads weekly. It was patched in versions 6.2.0 and 7.0.1 released earlier in August 2026, and full exploit details are withheld to prevent attacks. The V8 Isolate boundary itself held; the failure was in the C++ marshalling code bridging host and guest.

The Hacker News · 27d agoVulnerability

Telegram Desktop Flaw Lets Attackers Steal Chat Messages Through Poisoned HTML Exports

Telegram Desktop XSS in bot inline keyboard buttons let attackers steal chat content from exported HTML archives; patched in 7.0.1.

ExPatch researchers Denis and Aleksander Rostilov found a stored cross-site scripting flaw in Telegram Desktop's HTML export feature, present since version 4.15.1 (March 2024). JavaScript hidden in bot inline keyboard button text executes when a user opens an exported chat HTML file with JavaScript enabled, exposing messages, metadata, and enabling DOM manipulation such as fake verification screens. Fixes shipped in Desktop Beta 6.9.4 (July 3, 2026) and Stable 7.0.1 (July 14, 2026), but previously exported HTML files remain unsafe.

Cyber Security News · 1d agoVulnerability 2 sources

MapLibre Vulnerability Exposes 2.7M Users to Zero-Click Attacks

Critical XSS CVE-2026-85061 in MapLibre GL JS enables zero-click attacks on an estimated 2.7 million users; fixed in maplibre-gl 6.4.1.

A flaw in MapLibre GL JS's DOM.sanitize() iterates a live NamedNodeMap while removing attributes, skipping malicious attributes placed adjacent to removed ones, letting event handlers like onload and ontoggle survive and execute via innerHTML in the attribution control. Tracked as CVE-2026-85061 and GHSA-jrc7-96c5-q579, the flaw affects maplibre-gl versions 6.4.0 and earlier, is rated critical under CVSS v3.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N), and requires no user interaction, privileges, or authentication. Exploitation could enable session theft, unauthorized actions, phishing redirects, or map content manipulation; the patch in 6.4.1 snapshots attributes with Array.from before iterating.

Critical ArangoDB Bugs Expose Entire Databases and Enable Remote Code Execution as Root

Two critical ArangoDB flaws (CVSS 9.8/9.9) allow unauthenticated API access and root-level code execution; fixed in 3.12.11.

Remedio researchers reported two critical ArangoDB flaws on August 23, 2026: an authentication bypass via URL-encoded underscores (%5f) in path parsing (GHSA-rrgq-978q-36mq, CVSS 9.8) and a task-execution flaw where a client-controlled isSystem flag lets JavaScript run in the internal context (GHSA-rvhw-4hpw-9vrx, CVSS 9.9). Chained, they allow unauthenticated database access, theft of root password hashes, and root-level code execution when arangod runs as root, such as in the official container image. Patches shipped August 31 in ArangoDB 3.12.11, with GitHub Security Advisories published September 6; CVE identifiers were pending at disclosure time.

GBHackers · 7d agoVulnerability1

Chrome 153 Fixes 230 Vulnerabilities, Including One 0-Day Exploited in the Wild

Google shipped Chrome 153 with 230 fixes, including CVE-2026-87491, a V8 out-of-bounds write zero-day exploited in the wild.

Chrome 153 (153.0.8010.36/.37) rolls out to Windows, Mac, and Linux with 230 security fixes, among the largest patch batches in recent Chrome history. The headline flaw is CVE-2026-87491, a Medium-severity out-of-bounds write in the V8 JavaScript and WebAssembly engine that Google confirmed is exploited in the wild; it was reported by Jihyeon Jeong of Compsec Lab at Seoul National University for a $2,500 bounty. The release also closes five Critical-rated flaws, including CVE-2026-87464, CVE-2026-87488, CVE-2026-87438, CVE-2026-87527, and CVE-2026-87628, mostly use-after-free and out-of-bounds write bugs in WebGL and Cast, plus 43 High-severity issues across ANGLE, PDFium, V8, DevTools, and Payments. Several bugs were surfaced with AI-assisted discovery tools, including OpenAI's Codex Security team, and top bounties reached $5,000 for CVE-2026-87504.

Patch Tuesday - September 2026

Microsoft's September 2026 Patch Tuesday fixes 999 CVEs, a record, with two zero-day privilege escalation flaws already exploited in the wild.

Microsoft published 974 own-product vulnerabilities plus 25 non-Microsoft CVEs, totaling 999 — the most CVEs Microsoft has ever released in a single day. Two flaws are exploited in the wild: CVE-2026-85880, an out-of-bounds write in Windows ALPC granting SYSTEM privileges, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack also leading to SYSTEM. Chrome's V8 zero-day CVE-2026-85046 was patched in Edge on September 2, but Microsoft had not published a corresponding advisory, leaving uncertainty about other Chromium fixes in Edge. October 14 lifecycle changes end servicing for Windows 11 24H2 Home/Pro, Office 2021, and Exchange Server 2016/2019.

Rapid7 Blog · 7d agoVulnerability in the wildCVE-2026-85880CVE-2026-81963CVE-2026-85046+10 CVEs