fix(deps): update dependency next to v15.5.15 [security] - autoclosed

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
next (source)	15.5.14 → 15.5.15

GitHub Vulnerability Alerts

CVE-2025-59471

A DoS vulnerability exists in self-hosted Next.js applications that have remotePatterns configured for the Image Optimizer. The image optimization endpoint (/_next/image) loads external images entirely into memory without enforcing a maximum size limit, allowing an attacker to cause out-of-memory conditions by requesting optimization of arbitrarily large images. This vulnerability requires that remotePatterns is configured to allow image optimization from external domains and that the attacker can serve or control a large image on an allowed domain.

Strongly consider upgrading to 15.5.10 and 16.1.5 to reduce risk and prevent availability issues in Next applications.

GHSA-h25m-26qc-wcjf

A vulnerability affects certain React Server Components packages for versions 19.0.x, 19.1.x, and 19.2.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-2026-23864.

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

CVE-2026-29057

Summary

When Next.js rewrites proxy traffic to an external backend, a crafted DELETE/OPTIONS request using Transfer-Encoding: chunked could trigger request boundary disagreement between the proxy and backend. This could allow request smuggling through rewritten routes.

Impact

An attacker could smuggle a second request to unintended backend routes (for example, internal/admin endpoints), bypassing assumptions that only the configured rewrite destination/path is reachable. This does not impact applications hosted on providers that handle rewrites at the CDN level, such as Vercel.

Patches

The vulnerability originated in an upstream library vendored by Next.js. It is fixed by updating that dependency’s behavior so content-length: 0 is added only when both content-length and transfer-encoding are absent, and transfer-encoding is no longer removed in that code path.

Workarounds

If upgrade is not immediately possible:

• Block chunked DELETE/OPTIONS requests on rewritten routes at your edge/proxy.
• Enforce authentication/authorization on backend routes per our security guidance.

CVE-2026-27980

Summary

The default Next.js image optimization disk cache (/_next/image) did not have a configurable upper bound, allowing unbounded cache growth.

Impact

An attacker could generate many unique image-optimization variants and exhaust disk space, causing denial of service. Note that this does not impact platforms that have their own image optimization capabilities, such as Vercel.

Patches

Fixed by adding an LRU-backed disk cache with images.maximumDiskCacheSize, including eviction of least-recently-used entries when the limit is exceeded. Setting maximumDiskCacheSize: 0 disables disk caching.

Workarounds

If upgrade is not immediately possible:

• Periodically clean .next/cache/images.
• Reduce variant cardinality (e.g., tighten values for images.localPatterns, images.remotePatterns, and images.qualities)

GHSA-q4gf-8mx6-v5v3

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-2026-23869. You can read more about this advisory our this changelog.

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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Release Notes

vercel/next.js (next)

v15.5.15

Compare Source

Please refer the following changelogs for more information about this security release:

https://vercel.com/changelog/summary-of-cve-2026-23869

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