React Server Components are Vulnerable to RCE

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

10.0 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Summary @vitejs/plugin-rsc vendors react-server-dom-webpack, which contained an unauthenticated remote code execution vulnerability in versions prior to 19.0.1, 19.1.2, and 19.2.1. See details in React repository's advisory https://github.com/facebook/react/security/advisories/GHSA-fv66-9v8q-g76r Impact Applications using affected versions of @vitejs/plugin-rsc are vulnerable to unauthenticated remote code execution through deserialization of untrusted data. An attacker can execute arbitrary code remotely without authentication, affecting confidentiality, integrity, and availability. Recommendations Upgrade immediately to @vitejs/plugin-rsc@0.5.3 or later. Workarounds Applications not using server-side React or React Server Components are unaffected.

Published by the source

3 Dec 2025, 19:07 UTC

Last modified by the source

11 Dec 2025, 18:28 UTC

Source last checked

26 Oct 2026, 12:41 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-fmh4-wr37-44fp

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-fmh4-wr37-44fp

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-fmh4-wr37-44fp

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# Patch Next advisory brief: GHSA-fmh4-wr37-44fp

Advisory: React Server Components are Vulnerable to RCE
IDs: GHSA-fmh4-wr37-44fp
Record: https://patchnext.com/advisories/ghsa-fmh4-wr37-44fp (revision 3, source checked 26 Oct 2026, 12:41 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 10.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @vitejs/plugin-rsc 0.5.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @vitejs/plugin-rsc: affected <= 0.5.2; fixed in 0.5.3

## Suggested inspection (read-only)
- `npm ls @vitejs/plugin-rsc --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @vitejs/plugin-rsc.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-fmh4-wr37-44fp (GitHub-reviewed advisory GHSA-fmh4-wr37-44fp lists affected ranges: npm @vitejs/plugin-rsc >=0 <=0.5.2)
- Verified: https://osv.dev/vulnerability/GHSA-fmh4-wr37-44fp (OSV record GHSA-fmh4-wr37-44fp lists affected ranges: npm @vitejs/plugin-rsc >=0 <0.5.3 (fixed))

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