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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