Vulnerability · Published Jul 3, 2025 · Assigned by GitHub_M

CVE-2025-49826Next.js DoS vulnerability via cache poisoning

High 7.5

In plain English

A high-severity security flaw in next.js from vercel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 67% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)1.1%top 33.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Next.js is a React framework for building full-stack web applications. From versions 15.0.4-canary.51 to before 15.1.8, a cache poisoning bug leading to a Denial of Service (DoS) condition was found in Next.js. This issue does not impact customers hosted on Vercel. Under certain conditions, this issue may allow a HTTP 204 response to be cached for static pages, leading to the 204 response being served to all users attempting to access the page. This issue has been addressed in version 15.1.8.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	next	15.1.8	GHSA-67rr-84xm-4c7r

Affected products (as reported)

Vendor	Product	Versions
vercel	next.js	>= 15.0.4-canary.51, < 15.1.8

Weakness: CWE-444 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://github.com/vercel/next.js/security/advisories/GHSA-67rr-84xm-4c7r x_refsource_CONFIRM
https://github.com/vercel/next.js/commit/a15b974ed707d63ad4da5b74c1441f5b7b120e93 x_refsource_MISC
https://github.com/vercel/next.js/releases/tag/v15.1.8 x_refsource_MISC
https://vercel.com/changelog/cve-2025-49826 x_refsource_MISC