PT-2026-63563 · Npm · Next

CVE-2026-64648 · Published 2026-07-22 · Updated 2026-07-22

OSV

CVSS v4.0

6.0

Medium

Base vector

AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Impact

A server-side fetch with a request body may return a cached response body from a different request to the same URL but different body. Confidential data in the POST's response body would then leak to unauthorized requests. Though the request itself will not be deduped.

This only applies to fetch calls with a request that has a different init than the one passed to fetch. Safe: fetch(new Request(init), init) Unsafe: fetch(new Request(init), aDifferentInit)

Workarounds

No workaround exists besides upgrading. Applications using Pages Router are not vulnerable.

Fix

Weakness Enumeration

CWE-524

Related Identifiers

CVE-2026-64648

GHSA-68G3-V927-F742

Affected Products

Next

References · 7

• https://osv.dev/vulnerability/GHSA-68g3-v927-f742 · Vendor Advisory
• https://github.com/vercel/next.js/commit/73b94872bc343d09494b50394d8c08eb9fc8e56a · Note
• https://github.com/vercel/next.js/commit/062f66700b52a5d6bba2c0605d55577ab7ad262c · Note
• https://github.com/vercel/next.js/security/advisories/GHSA-68g3-v927-f742 · Note
• https://github.com/vercel/next.js/releases/tag/v16.2.11 · Note
• https://github.com/vercel/next.js · Note
• https://github.com/vercel/next.js/releases/tag/v15.5.21 · Note