cvedb.io
CVE-2026-21717
MEDIUM · CVSS 5.9
EPSS exploitation probability: 0%
Published 2026-03-30T20:16:20.010 · Last modified 2026-06-17T10:18:57.890

Summary

A flaw in V8's string hashing mechanism causes integer-like strings to be hashed to their numeric value, making hash collisions trivially predictable. By crafting a request that causes many such collisions in V8's internal string table, an attacker can significantly degrade performance of the Node.js process. The most common trigger is any endpoint that calls `JSON.parse()` on attacker-controlled input, as JSON parsing automatically internalizes short strings into the affected hash table. This vulnerability affects **20.x, 22.x, 24.x, and 25.x**.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.