CVE-2024-3651 MEDIUM

CVE-2024-3651: Denial of Service via Quadratic Complexity in kjd/idna

Vendor Kjd
Product kjd/idna
Weakness CWE-1333
Published July 7, 2024
Last update November 4, 2025

CVSS base score

6.2/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

A vulnerability was identified in the kjd/idna library, specifically within the `idna.encode()` function, affecting version 3.6. The issue arises from the function's handling of crafted input strings, which can lead to quadratic complexity and consequently, a denial of service condition. This vulnerability is triggered by a crafted input that causes the `idna.encode()` function to process the input with considerable computational load, significantly increasing the processing time in a quadratic manner relative to the input size.

Key dates

02Disclosure timeline

July 7, 2024 CVE published
November 4, 2025 Record updated