CVE-2026-64645: Next.js is a React framework for building full-stack web applications

Q: How do I fix CVE-2026-64645?

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

Q: Is CVE-2026-64645 being exploited?

CVE-2026-64645 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-64645 affect?

CVE-2026-64645 affects next.js. Severity is medium (CVSS 6.1). Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a rewrites() or redirects() rule that builds its external destination hostname from request-controlled in

Q: How urgent is CVE-2026-64645?

Priority 30/100. No elevated risk signals yet.

Routine

MEDIUM 6.1UPGRADE

CVE-2026-64645 is a medium-severity flaw (CVSS 6.1) 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 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a rewrites() or redirects() rule that builds its external destination hostname from request-controlled input can be pointed at an arbitrary hostname, regardless of the rule's hostname suffix. For a rewrite, Next.js proxies the request to that arbitrary host and serves the response from the application's origin, le

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.4% (top 65%)
CISA exploited list	No
Weakness	CWE-601, 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 18:16 UTCPublished CVE record published
2026-10-24 13:10 UTCUpdated Record last modified

vercel next.js UPGRADE

Affected: >= 12.0.0 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 12.0.0

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 12.0.0

npm view next.js versions npm install next.js@"<12.0.0"

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.

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-2026-64645?

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

Is CVE-2026-64645 being exploited?

CVE-2026-64645 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-2026-64645 affect?

CVE-2026-64645 affects next.js. Severity is medium (CVSS 6.1). Next.js is a React framework for building full-stack web applications. In versions 12.0.0 through 15.5.20 and 16.0.0 through 16.2.10, a rewrites() or redirects() rule that builds its external destination hostname from request-controlled in

How urgent is CVE-2026-64645?

Priority 30/100. No elevated risk signals yet.

Software pages

React vulnerabilities · Next.js 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-2026-64649 MEDIUM 6.5 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

References

← Back to latest CVEs