Deserialization in Facebook React

CVE-2026-23864

Multiple denial of service vulnerabilities exist in React Server Components, affecting the following packages: react-server-dom-parcel, react-server-dom-turbopack, react-server-dom-webpack. The vulnerabilities are triggered by sending specially crafted HTTP requests to Server Function endpoints, and could lead to server crashes, out-of-memory exceptions or excessive CPU usage; depending on the vulnerable code path being exercised, the application configuration and application code. Strongly consider upgrading to the latest package versions to reduce risk and prevent availability issues in applications using React Server Components.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.026 (84.6th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 85th percentile — 84.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-23864: held from 0.024 to 0.026.

EPSS over last 30 days · oldest: 0.024 · newest: 0.026 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-23864?
CVE-2026-23864 is a high-severity vulnerability in Facebook React, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-01-26.
How severe is CVE-2026-23864?
High severity. CVSS v3 base score is 7.5 out of 10.