Use of cache containing sensitive information in Next.js - CVE-2026-64648
Published: July 22, 2026
Vulnerability identifier: #VU139031
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-64648
CWE-ID: CWE-524
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: vercel
Affected software:
Next.js
Next.js
Detailed vulnerability description
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to improper cache key generation in the server-side fetch cache when processing fetch requests with a request body and a different init than the one used to create the Request object. A remote attacker can send a specially crafted request to disclose sensitive information.
User interaction is required, and only server-side fetch calls using a Request object together with a different init are affected. Applications using Pages Router are not vulnerable.
How to mitigate CVE-2026-64648
Install security update from vendor's website.