CVE-2026-21717 in Node.js
Riassunto
di MITRE • 30/03/2026
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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