Skip to content
Fencer Vulns
high 7.5

CVE-2025-49826 json

Next.js DoS vulnerability via cache poisoning

published 2025-07-03 16 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-19910 , GHSA-67rr-84xm-4c7r

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.1%
EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits
0
none known

Summary

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.

Patch / fix

  • npm next 15.1.8
  • vercel next.js 15.1.8

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-49826 updated cvss 5.3

nextjs: Next.js denial of service

  • Red Hat Enterprise Linux 7 firefox Red Hat Enterprise Linux 8 firefox, thunderbird Red Hat Enterprise Linux 9 firefox, firefox-x11, thunderbird Red Hat Enterprise Linux 10 firefox, thunderbird Red Hat Enterprise Linux AI (RHEL AI) rhelai1/ui-rhel9, rhelai1/granite-8b-lab-v1, rhelai1/pathservice-rhel9, rhelai1/skills-adapter-v3, rhelai1/granite-7b-starter, rhelai1/docling-serve-rhel9, +23 more
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Enterprise Linux 9 dotnet7.0, dotnet-host, dotnet-sdk-7.0, dotnet-hostfxr-7.0, dotnet-runtime-7.0, dotnet-templates-7.0, +6 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
16 mo ago

Exploit prediction

1.13% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
npm next
>=15.0.4-canary.51, <15.1.8
15.1.8

Affected products

  • vercel next.js

Classification

Weakness
  • CWE-444 Inconsistent Interpretation of HTTP Requests
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of vercel/next.js published their own advisory on GitHub. Reviewed sources take precedence over it.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.