MSHTML security feature bypass exploited in the wild

high severity · exploited in the wild · published 2026-02-10

Attackers can bypass security protections in the MSHTML framework to run malicious code when you view crafted web content or documents. This vulnerability is actively exploited in the wild.

Fixed in: 10.0.28000.1575

CVE: CVE-2026-21513

Source: Microsoft (MSRC)

Am I affected?

You are affected if the installed version is older than 10.0.28000.1575. Check the version you have and update to 10.0.28000.1575 or later. The fixed version is verified against a vendor or advisory source.

Get the fix

FixLane has a reviewed fix procedure for this incident: a read-only check first, then the fix. Ask the Telegram bot, or connect an AI agent to the FixLane MCP server and call get_fix_prompt with incident id 1576 and your operating system.