Resource exhaustion in Nuxt

CVE-2026-71321

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.

EPSS: 0.004 (36.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

  • Nuxt — versions >= 4.0.0, < 4.5.1, >= 3.1.0, < 3.21.10

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-71321?
CVE-2026-71321 is a high-severity vulnerability in Nuxt, classified under Inefficient Algorithmic Complexity. CVSS score: 7.5/10. Published 2026-08-05.
How severe is CVE-2026-71321?
High severity. CVSS v3 base score is 7.5 out of 10.