AIKIDO-2026-467347
next is vulnerable to Sensitive Information Disclosure
63
Medium Risk
This Affects:
nextTL;DR
Next.js derives the cache key for server-side fetch responses from a text decoding of the request body that loses information for non-UTF-8 byte sequences. Distinct request bodies that decode to the same lossy text share a cache entry, so a fetch to the same URL with a different body can return another request's cached response body. Confidential data from one POST response can then leak to unauthorized callers. The fix keys the cache on the raw body bytes so differing bodies no longer collide. Applications using the Pages Router are not affected.
Who does this affect?
You are affected if you are using a version that falls within the vulnerable range and your application uses the App Router with server-side fetch calls whose request bodies are not UTF-8 encoded.
Background info
next is vulnerable to Sensitive Information Disclosure in versions 13.0.0 - 15.5.20 and 16.0.0 - 16.2.10.
How to fix this
Upgrade the next library to the patch version.
Are You Affected?
Connect your repositories to instantly see whether vulnerable or malicious packages exist in your codebase.
Free. No credit card required.
I consent to receiving marketing communications based on Aikido’s Privacy Policy.
SOC 2Compliant
ISO 27001Compliant