CVE-2026-44581

Next.js: Cross-site scripting in App Router applications using CSP nonces

Published May 13, 2026 CVSS 3.1 · 4.7 Medium EPSS < 1% KEV · Not listed
Description
Next.js is a React framework for building full-stack web applications. From 13.4.0 to before 15.5.16 and 16.2.5, App Router applications that rely on CSP nonces can be vulnerable to stored cross-site scripting when deployed behind shared caches. In affected versions, malformed nonce values derived from request headers could be reflected into rendered HTML in an unsafe way, allowing an attacker to poison cached responses and cause script execution for later visitors. This vulnerability is fixed in 15.5.16 and 16.2.5.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-ffhc-5mcf-pf4q Next.js vulnerable to cross-site scripting in App Router applications using CSP nonces
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
CPEs cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*
Type Values Removed Values Added
First Time appeared Vercel
Vercel next.js
Vendors & Products Vercel
Vercel next.js
Type Values Removed Values Added
Description Next.js is a React framework for building full-stack web applications. From 13.4.0 to before 15.5.16 and 16.2.5, App Router applications that rely on CSP nonces can be vulnerable to stored cross-site scripting when deployed behind shared caches. In affected versions, malformed nonce values derived from request headers could be reflected into rendered HTML in an unsafe way, allowing an attacker to poison cached responses and cause script execution for later visitors. This vulnerability is fixed in 15.5.16 and 16.2.5.
Title Next.js: Cross-site scripting in App Router applications using CSP nonces
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 18, 2026, 2:13 PM
Reserved
May 6, 2026, 9:49 PM
Status
Analyzed
Published
May 13, 2026, 6:16 PM
Modified
Oct 26, 2026, 2:10 PM
Severity
Moderate
Public date
May 13, 2026, 5:07 PM