CVE-2021-21240

HIGH

httplib2 < 0.19.0 - Denial of Service via Malicious WWW-Authenticate Header

Title source: llm
STIX 2.1

Description

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.

References (4)

Core 4
Core References
Exploit, Mitigation, Third Party Advisory x_refsource_confirm
https://github.com/httplib2/httplib2/security/advisories/GHSA-93xj-8mrv-444m
Patch, Third Party Advisory x_refsource_misc
https://github.com/httplib2/httplib2/pull/182
Product, Third Party Advisory x_refsource_misc
https://pypi.org/project/httplib2

Scores

CVSS v3 7.5
EPSS 0.0388
EPSS Percentile 88.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE
CWE-400
Status published
Products (2)
httplib2_project/httplib2 < 0.19.0
pypi/httplib2 0 - 0.19.0PyPI
Published Feb 08, 2021
Tracked Since Feb 18, 2026