CVE-2026-21717
Published: Mar 30, 2026
Modified: May 10, 2026
CVSS v3.0
5.9
Description
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**.
| Vendor | Product | Versions |
|---|---|---|
nodejs | node | affected 20.20.1 - <= 20.20.1affected 22.22.1 - <= 22.22.1affected 24.14.0 - <= 24.14.0affected 25.8.1 - <= 25.8.1affected 4.0 - < 4.*+15 more versions |
CVSS v3.0 Details
CVSS v3.0 Vector
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Security Training
Train your team to recognize and prevent security threats with our comprehensive security awareness program.
Start TrainingVulnerability Scanning
Discover vulnerabilities in your applications and infrastructure before attackers do.
Scan Now