CVE-2024-34350: next.js Request Smuggling — Fix

Description

Next.js is a React framework that can provide building blocks to create web applications. Prior to 13.5.1, an inconsistent interpretation of a crafted HTTP request meant that requests are treated as both a single request, and two separate requests by Next.js, leading to desynchronized responses. This led to a response queue poisoning vulnerability in the affected Next.js versions. For a request to be exploitable, the affected route also had to be making use of the [rewrites](https://nextjs.org/docs/app/api-reference/next-config-js/rewrites) feature in Next.js. The vulnerability is resolved in Next.js `13.5.1` and newer.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-444 CWE-444

Affected Products

Vendor	Product	Versions
vercel	next.js	13.4.0 — 13.5.1

References

Advisories & Patches

https://github.com/vercel/next.js/security/advisories/GHSA-77r5-gw3j-2mpf https://github.com/vercel/next.js/security/advisories/GHSA-77r5-gw3j-2mpf

Frequently Asked Questions

What is CVE-2024-34350? +

Next.js is a React framework that can provide building blocks to create web applications. Prior to 13.5.1, an inconsistent interpretation of a crafted HTTP request meant that requests are treated as both a single request, and two separate requests by Next.js, leading to desynchronized responses. This led to a response queue poisoning vulnerability in the affected Next.js versions. For a request to be exploitable, the affected route also had to be making use of the [rewrites](https://nextjs.org/docs/app/api-reference/next-config-js/rewrites) feature in Next.js. The vulnerability is resolved in Next.js `13.5.1` and newer. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2024-34350? +

CVE-2024-34350 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-34350? +

CVE-2024-34350 affects products from vercel, specifically: next.js. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-34350? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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