Answer in brief
CVE-2026-23870 records a High severity (CVSS 7.5) vulnerability in Denial of Service Vulnerability in React Server Components. The current sources do not mark it as known exploited. The current feed maps react-server-dom-parcel (npm), react-server-dom-turbopack (npm), react-server-dom-webpack (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps react-server-dom-parcel (npm), react-server-dom-turbopack (npm), react-server-dom-webpack (npm). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:a:facebook:react-server-dom-parcel:*:*:*:*:*:node.js:*:* | Not reported | Not reported |
| cpe:2.3:a:facebook:react-server-dom-turbopack:*:*:*:*:*:node.js:*:* | Not reported | Not reported |
| cpe:2.3:a:facebook:react-server-dom-webpack:*:*:*:*:*:node.js:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| react-server-dom-parcelnpm | 19.0.0,19.0.1,19.0.2,19.0.3,19.0.4,19.0.5,19.1.0,19.1.1,19.1.2,19.1.3,19.1.4,19.1.5,19.1.6,19.2.0,19.2.1,19.2.2,19.2.3,19.2.4,19.2.5 | Not reported |
| react-server-dom-turbopacknpm | 19.0.0,19.0.1,19.0.2,19.0.3,19.0.4,19.0.5,19.1.0,19.1.1,19.1.2,19.1.3,19.1.4,19.1.5,19.1.6,19.2.0,19.2.1,19.2.2,19.2.3,19.2.4,19.2.5 | Not reported |
| react-server-dom-webpacknpm | 19.0.0,19.0.1,19.0.2,19.0.3,19.0.4,19.0.5,19.1.0,19.1.1,19.1.2,19.1.3,19.1.4,19.1.5,19.1.6,19.2.0,19.2.1,19.2.2,19.2.3,19.2.4,19.2.5 | Not reported |
Published upstream
May 6, 2026
Evidence: source:ghsa:source_dates:source-dates:recordSource modified
Aug 12, 2026
Evidence: source:ghsa:source_dates:source-dates:recordFirst seen by HOL
Aug 12, 2026
## Impact A denial of service vulnerability could be triggered by sending specially crafted HTTP requests to server function endpoints, this could lead to out-of-memory exceptions or excessive CPU usage. We recommend updating immediately. The vulnerability exists in versions 19.0.0 through 19.0.5, 19.1.0 through 19.1.6, and 19.2.0 through 19.2.5 of: [react-server-dom-webpack](https://www.npmjs.com/package/react-server-dom-webpack) [react-server-dom-parcel](https://www.npmjs.com/package/react-server-dom-parcel) [react-server-dom-turbopack](https://www.npmjs.com/package/react-server-dom-turbopack?activeTab=readme) ## Patches Fixes were back ported to versions 19.0.6, 19.1.7, and 19.2.6. If you are using any of the above packages please upgrade to any of the fixed versions immediately. If your app’s React code does not use a server, your app is not affected by this vulnerability. If your app does not use a framework, bundler, or bundler plugin that supports React Server Components, your app is not affected by this vulnerability. References See the [blog post](https://react.dev/blog/2025/12/11/denial-of-service-and-source-code-exposure-in-react-server-components) for more information and upgrade instructions.
Quoted source text, attributed separately from HOL analysis.