Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Low severity, with a CVSS score of 3.1, published 11 May 2026.

Which products and versions are affected?

@vitejs/plugin-rsc (npm) SEMVER:introduced=0,fixed=0.5.26.

Is there a fix for This vulnerability?

Yes. @vitejs/plugin-rsc (npm): upgrade to 0.5.26 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network, in a software library.

Check whether you run @vitejs/plugin-rsc (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Vitejs plugin-rsc denial of service in React Server Components

Severity: low · CVSS 3.1 · Published 2026-05-11

@vitejs/plugin-rsc is a Vite plugin that handles React Server Components, used by developers building server-rendered React applications. A vulnerability in the bundled react-server-dom-webpack library allows attackers to send specially crafted HTTP requests that trigger excessive CPU usage, causing the application to become unresponsive and denying service to legitimate users.

Technologies: @vitejs/plugin-rsc (npm). Vendors: npm.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Low severity, with a CVSS score of 3.1, published 11 May 2026.
Which products and versions are affected?: @vitejs/plugin-rsc (npm) SEMVER:introduced=0,fixed=0.5.26.
Is there a fix for This vulnerability?: Yes. @vitejs/plugin-rsc (npm): upgrade to 0.5.26 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network, in a software library.
Am I affected?: Check whether you run @vitejs/plugin-rsc (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

@vitejs/plugin-rsc (npm): upgrade to 0.5.26 or later
```
npm install @vitejs/plugin-rsc@0.5.26
```

Technical details

The vulnerability is a resource exhaustion issue (CWE-770) in the react-server-dom-webpack library vendored by @vitejs/plugin-rsc versions prior to 19.2.6. When a specially crafted HTTP request is deserialized by an affected App Router Server Function endpoint, it triggers excessive CPU consumption without any rate limiting or resource constraints. The attack requires only network access with no authentication or user interaction; an attacker can remotely send malicious requests to trigger denial of service. The fix is available in @vitejs/plugin-rsc 0.5.26 and later, which updates the vendored react-server-dom-webpack to a patched version.

Affected products

Vitejs plugin-rsc prior to 0.5.26

Timeline

2026-05-07: disclosed
2026-05-07: patched: Available in @vitejs/plugin-rsc 0.5.26 and later

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.