HighGHSA-8h8q-6873-q5fj

Next.js Vulnerable to Denial of Service with Server Components

Published 11 May 2026 · Updated 10 Sept 2026

Affected packages

nextnpm

Affected: >=13.0.0 <15.5.16
Fixed in: 15.5.16

Update to the fixed version for your release line, for example:npm install next@15.5.16

nextnpm

Affected: >=16.0.0 <16.2.5
Fixed in: 16.2.5

Update to the fixed version for your release line, for example:npm install next@16.2.5

Details

A vulnerability affects certain React Server Components packages for versions 19.x and frameworks that use the affected packages, including Next.js 13.x, 14.x, 15.x, and 16.x using the App Router. The issue is tracked upstream as CVE-2026-23870.

A specially crafted HTTP request can be sent to any App Router Server Function endpoint that, when deserialized, may trigger excessive CPU usage. This can result in denial of service in unpatched environments.

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.