react
: Unauthenticated Remote Code Execution in React Server Components
Not on CISA's list of exploited flaws, and not in the news we track.
CVE-2026-126187Critical9.5
Black Shard's team can check your exposure to CVE-2026-126187 and take the fix off your plate.
React is a JavaScript library for building user interfaces. From 19.0.0 until 19.0.9, 19.1.10, 19.2.9, and 19.3.1, the react-server-dom-webpack, react-server-dom-parcel, and react-server-dom-turbopack packages are vulnerable to unauthenticated remote code execution through crafted payloads targeting frameworks that support React Server Components. The vulnerability only affects extremely rare cases where responses transport multiple typed arrays and an attacker-controlled value. Applications whose React code does not use a server are not affected. Applications that do not use a framework, bundler, or bundler plugin that supports React Server Components are not affected. This issue is fixed in versions 19.0.9, 19.1.10, 19.2.9, and 19.3.1.
Black Shard's team can check your exposure, take a fix off your plate or step in on a live incident.
Chance of exploitation in the next 30 days
1.8%
EPSS score from FIRST
Updated 13 Nov 2026, 12:02 UTC, 30 of 36 sources answering.
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