WatchWATCH-next-upcoming-nextjs-security-release-september-202623 Sep · 30 days ago
Source ↗

Upcoming Next.js September Security Release.

Does it affect you?

Not read yet

Conditions are read within the hour after an advisory comes in.

Next.js is preparing a scheduled September security release for September 30, 2026.

Sourcesnextjs.org

Timeline

23 Sep
30 daysfrom publication to Patchwire
  1. Published by nextjs.org23 Sep
  2. Seen by Patchwire23 Oct

Versions in the source

Packages

Stacks

Related alerts(8)

Same packages
High
Exploitable only if · read by Claude, the source remains the reference
  • Next.js application uses the App Router.
  • Application defines at least one Server Action.
  • Next.js version is an unpatched (vulnerable) release.
Affected
next >=13.0.0 <=15.5.27 · next >=16.0.0 <=16.4.0
Fixed in
15.5.28 · 16.4.1
ID
GHSA-p3m5-59mp-jv5r
Open the alert
Critical
Conditions not read yet

Source summary

Impact A vulnerability in applications using App router with Cache Component can lead to remote code execution. The application needs to have a use cache function that returns multiple typed arrays. Workaround There is no known workaround for affected applications with such use cache functions. You should upgrade immediately even if your application does not have similar functions.

Affected
next >=16.0.0 <=16.4.0
Fixed in
16.4.1
ID
GHSA-673q-mjm6-r5xr
Open the alert
Critical
Conditions not read yet

Source summary

Impact A memory-related vulnerability has been discovered in an upstream library used for Image Optimization can lead to possible remote code execution (RCE) when Next.js runs on glibc-based Linux. Workaround Ensure the version of sharp used by Next.js is greater than or equal to 0.35.5 . Fresh installs automatically get a fixed version of sharp . Upgrading Next.js to the patched versions will ensure package managers automatically provide a fixed version of sharp to Next.js.

Affected
next >=10.0.0 <=15.5.27 · next >16.0.0 <=16.4.0 · next >=16.0.0 <=16.4.0
Fixed in
15.5.28 · 16.4.1
ID
GHSA-2464-fhr4-w9xw
Open the alert
Watch
Conditions not read yet

Source summary

Next.js plans to publish an out-of-band security update next Wednesday, October 14, 2026, addressing two Critical and one High severity vulnerabilities in upstream dependencies.

Affected
in the source
Fixed in
no fix yet
ID
WATCH-next-upcoming-nextjs-security-update-october-2026
Open the alert
High
Conditions not read yet

Source summary

Impact An attacker-controlled, allow-listed remote URL can lead to server-side request forgery (e.g. to private IPs) during Image Optimization. Workaround Audit allow-listed remote URLs in images.remotePatterns (see https://nextjs.org/docs/app/getting-started/images remote-images) for hosts that may not be trusted with their DNS entries. If no images.remotePatterns are configured, your app is not affected.

Affected
next >=16.0.0 <16.3.8
Fixed in
16.3.8
ID
GHSA-cjq9-62q9-8jv4
Open the alert
Medium
Conditions not read yet

Source summary

In Next.js App Router applications built with webpack, metadata image routes such as opengraph-image and twitter-image ignore the dynamicParams route segment option. An attacker can request metadata image URLs for dynamic segments that were deliberately excluded from generateStaticParams() .

Affected
next >=16.0.0 <16.3.8
Fixed in
16.3.8
ID
GHSA-f87g-xv8r-7p7x
Open the alert
Medium
Conditions not read yet

Source summary

Pending use cache fills are shared across requests for the same key without distinguishing Draft Mode requests from regular requests. When two such requests overlap, the second request receives the first request's fill: - A regular request that overlaps an editor's Draft Mode request receives unpublished content, without any authentication. - A Draft Mode request that overlaps a regular request receives published content instead of the draft. If the overlapping regular request prerenders a page: for example an on-demand prerender of a route that was not prerendered at build time: the unpubli

Affected
next >=16.3.0 <16.3.8
Fixed in
16.3.8
ID
GHSA-3w37-wq28-93x7
Open the alert
Medium
Conditions not read yet

Source summary

Impact With Cache Components enabled ( cacheComponents: true ), a 'use cache' function that calls another 'use cache' function that reads a root param can be keyed incorrectly when the inner call is served from an existing entry: the enclosing function's cache key then omits that root param. The enclosing entry is written once and reused for all root param values, so a response for one root param value can serve content produced for a different value: whether the page is prerendered at build time or at runtime, or rendered dynamically. Shared cache headers let downstream caches redistribute t

Affected
next 16.3.0 · next >=16.3.0 <16.3.8
Fixed in
16.3.8
ID
GHSA-h694-7cp9-m8p3
Open the alert