CVE-2021-21240 HIGH

CVE-2021-21240: Regular Expression Denial of Service in httplib2

Vendor Httplib2
Product httplib2
Weakness CWE-400
Published February 8, 2021
Last update August 3, 2024

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

httplib2 is a comprehensive HTTP client library for Python. In httplib2 before version 0.19.0, a malicious server which responds with long series of "\xa0" characters in the "www-authenticate" header may cause Denial of Service (CPU burn while parsing header) of the httplib2 client accessing said server. This is fixed in version 0.19.0 which contains a new implementation of auth headers parsing using the pyparsing library.

Key dates

02Disclosure timeline

February 8, 2021 CVE published
August 3, 2024 Record updated