CVE-2026-64649: Next.js is a React framework for building full-stack web applications

Routine

MEDIUM 6.5REMOTEUPGRADE

CVE-2026-64649 is a medium-severity flaw (CVSS 6.5) affecting next.js. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Next.js is a React framework for building full-stack web applications. In versions 14.1.1 through 15.5.20 and 16.0.0 through 16.2.10, when a Server Action forwards or redirects a request, an attacker can cause the server to send that outbound request to a malicious host (Server-Side Request Forgery). This requires the attacker's request to control Host-associated headers. In some configurations, it's also possible to obtain internal values that w

Why this priority

Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 61%)
CISA exploited list	No
Weakness	CWE-918
Published	2026-07-27
Last modified	2026-10-24

Publisher (CNA): GitHub, Inc. · Vendor: vercel

Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-07-27 20:16 UTCPublished CVE record published
2026-10-24 13:10 UTCUpdated Record last modified

vercel next.js UPGRADE

Affected: >= 14.1.1 and < 15.5.21 · >= 16.0.0 and < 16.2.11

Fixed in: 15.5.21, 16.2.11

Safe to downgrade to: a release before 14.1.1

1. Check installed version

npm ls next.js

2. UPGRADE to 15.5.21

npm install next.js@">=15.5.21"

3. If no update is available yet, DOWNGRADE to a release before 14.1.1

npm view next.js versions npm install next.js@"<14.1.1"

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Exact fixes by distribution

npm · next · FIXED · 15.5.21 · vulnerable: >= 14.1.1, < 15.5.21 · source

npm install next@">=15.5.21" npm ls next

Fedora 46 · sugar-toolkit-gtk3 · FIXED · 0.122-2.fc46 · FEDORA-2026-d11eb2faf0 · source

sudo dnf upgrade --advisory=FEDORA-2026-d11eb2faf0

Fedora ELN · ntpd-rs · FIXED · 1.7.2-3.eln159 · FEDORA-2026-57e4a99310 · source

sudo dnf upgrade --advisory=FEDORA-2026-57e4a99310

RHEL 10 · firefox · NOT AFFECTED

RHEL 10 · thunderbird · NOT AFFECTED

RHEL 7 · firefox · NOT AFFECTED

RHEL 8 · firefox · NOT AFFECTED

RHEL 8 · thunderbird · NOT AFFECTED

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-64649?

next.js: upgrade to 15.5.21, 16.2.11. Exact commands for each OS are on this page.

Is CVE-2026-64649 being exploited?

CVE-2026-64649 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-64649 affect?

CVE-2026-64649 affects next.js. Severity is medium (CVSS 6.5). Next.js is a React framework for building full-stack web applications. In versions 14.1.1 through 15.5.20 and 16.0.0 through 16.2.10, when a Server Action forwards or redirects a request, an attacker can cause the server to send that outbou

How urgent is CVE-2026-64649?

Priority 37/100. Remotely exploitable, no login, no user action

Software pages

React vulnerabilities

Related CVEs

CVE-2026-64641 HIGH 7.5 UPGRADE Next.js is a React framework for building full-stack web applications
CVE-2026-64642 HIGH 8.2 UPGRADE Next.js is a React framework for building full-stack web applications
CVE-2026-64644 MEDIUM 5.3 UPGRADE Next.js is a React framework for building full-stack web applications
CVE-2026-64643 MEDIUM 5.3 UPGRADE Next.js is a React framework for building full-stack web applications
CVE-2026-64646 MEDIUM 5.3 UPGRADE Next.js is a React framework for building full-stack web applications

References

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