Vulnerability · Published Apr 8, 2026 · Assigned by Meta

CVE-2026-23869

High 7.5

In plain English

A high-severity unsafe deserialization in react-server-dom-parcel from Meta. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.6% (higher than 76% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)1.6%top 24.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack tooling1Public PoC

Official description

A denial of service vulnerability exists in React Server Components, affecting the following packages: react-server-dom-parcel, react-server-dom-turbopack and react-server-dom-webpack (versions 19.0.0 through 19.0.4, 19.1.0 through 19.1.5, and 19.2.0 through 19.2.4). The vulnerability is triggered by sending specially crafted HTTP requests to Server Function endpoints.The payload of the HTTP request causes excessive CPU usage for up to a minute ending in a thrown error that is catchable.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
npmreact-server-dom-parcel19.0.5GHSA-479c-33wc-g2pg
npmreact-server-dom-parcel19.1.6GHSA-479c-33wc-g2pg
npmreact-server-dom-parcel19.2.5GHSA-479c-33wc-g2pg
npmreact-server-dom-turbopack19.0.5GHSA-479c-33wc-g2pg
npmreact-server-dom-turbopack19.1.6GHSA-479c-33wc-g2pg
npmreact-server-dom-turbopack19.2.5GHSA-479c-33wc-g2pg
npmreact-server-dom-webpack19.0.5GHSA-479c-33wc-g2pg
npmreact-server-dom-webpack19.1.6GHSA-479c-33wc-g2pg
npmreact-server-dom-webpack19.2.5GHSA-479c-33wc-g2pg

Affected products (as reported)

VendorProductVersions
Meta react-server-dom-turbopack 19.0.0 – through 19.0.419.1.0 – through 19.1.519.2.0 – through 19.2.4
Meta react-server-dom-parcel 19.0.0 – through 19.0.419.1.0 – through 19.1.519.2.0 – through 19.2.4
Meta react-server-dom-webpack 19.0.0 – through 19.0.419.1.0 – through 19.1.519.2.0 – through 19.2.4

Weakness: CWE-502, CWE-400, CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References