Vulnerability Description
Nuxt is an open-source web development framework for Vue.js. From 3.1.0 until 3.21.10 and 4.5.1, the internal island renderer endpoint `/__nuxt_island/...` decodes and hashes attacker-controlled JSON body input with destr and ohash before validating the URL-resident hash. An unauthenticated `POST /__nuxt_island/_.json` with a large JSON body is fully read, parsed, hashed, and then rejected, which wastes CPU on Nitro single event loop and delays concurrent requests. No valid hash and no authentication are required. This issue is fixed in 3.21.10 and 4.5.1.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/nuxt/nuxt/commit/4e35ae9babd94be53246e31200232d48438bb34e
- https://github.com/nuxt/nuxt/commit/668cdfdfda41849ed11c1ee5e2067a11fc103b22
- https://github.com/nuxt/nuxt/releases/tag/v3.21.10
- https://github.com/nuxt/nuxt/releases/tag/v4.5.1
- https://github.com/nuxt/nuxt/security/advisories/GHSA-9pgf-384g-p7mv
FAQ
What is CVE-2026-71321?
CVE-2026-71321 is a vulnerability with a CVSS score of 7.5 (HIGH). Nuxt is an open-source web development framework for Vue.js. From 3.1.0 until 3.21.10 and 4.5.1, the internal island renderer endpoint `/__nuxt_island/...` decodes and hashes attacker-controlled JSON ...
How severe is CVE-2026-71321?
CVE-2026-71321 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-71321?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.