CVE-2026-44578

Next.js: Server-side request forgery in applications using WebSocket upgrades

Next.js is a React framework for building full-stack web applications. From 13.4.13 to before 15.5.16 and 16.2.5, self-hosted applications using the built-in Node.js server can be vulnerable to server-side request forgery through crafted WebSocket upgrade requests. An attacker can cause the server to proxy requests to arbitrary internal or external destinations, which may expose internal services or cloud metadata endpoints. Vercel-hosted deployments are not affected. This vulnerability is fixed in 15.5.16 and 16.2.5.

Affected

vercel · next.js

CVSS v3.1 CNA

8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

EPSS

1.90% chance of exploitation in the next 30 days, 79th percentile

Nuclei

high · CWE-918

Published

2026-05-13

Updated

2026-08-13

Proof-of-concept exploits (6)

• love07oj/nextjs-cve-2026-445788★ · 2026-05-15
• 0xBlackash/CVE-2026-445781★ · 2026-05-17
• tocong282/CVE-2026-44578-PoC0★ · 2026-05-15
• lxxexxbxx/CVE-2026-445781★ · 2026-08-20
• isaca0315/CVE-2026-44578-next-js-ssrf0★ · 2026-09-06
• dinosn/CVE-2026-44578/blob/b0dac63cf161c442b7042037aa44ec80860d4375/exploit/poc.py9★ · 2026-05-16

Nuclei templates (1)

• projectdiscovery/nuclei-templates/blob/main/javascript/cves/2026/CVE-2026-44578.yaml

Security advisories

• vercel/next.js/security/advisories/GHSA-c4j6-fc7j-m34r
• advisories/GHSA-c4j6-fc7j-m34r

References

• CVE Record
• NVD entry

Related

• CVE-2026-33017
• CVE-2026-44351
• CVE-2026-44840
• CVE-2026-64849
• CVE-2026-65013
• CVE-2019-13132