vulnerability
Red Hat: CVE-2021-21240: python-httplib2: Regular expression denial of service via malicious header
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 5 | (AV:N/AC:L/Au:N/C:N/I:N/A:P) | Feb 8, 2021 | Jul 9, 2025 | Jul 9, 2025 |
Severity
5
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:P)
Published
Feb 8, 2021
Added
Jul 9, 2025
Modified
Jul 9, 2025
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.
Solution
no-fix-redhat-rpm-package
References
Rapid7 Labs
2026 Global Threat Landscape Report
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