CVE-2026-21717
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
30/03/2026
Last modified:
10/05/2026
Description
A flaw in V8&#39;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&#39;s internal string table, an attacker can significantly degrade performance of the Node.js process.<br />
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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.<br />
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This vulnerability affects **20.x, 22.x, 24.x, and 25.x**.
Impact
Base Score 3.x
5.90
Severity 3.x
MEDIUM