CVE-2021-21240
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (3.63%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 3.63% probability · 89th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400
- Affected
- httplib2 project/httplib2
- Source
- security-advisories@github.com
References
- https://github.com/httplib2/httplib2/commit/bd9ee252c8f099608019709e22c0d705e98d26bcPatch, Third Party Advisory
- https://github.com/httplib2/httplib2/pull/182Patch, Third Party Advisory
- https://github.com/httplib2/httplib2/security/advisories/GHSA-93xj-8mrv-444mExploit, Mitigation, Third Party Advisory
- https://pypi.org/project/httplib2Product, Third Party Advisory
- https://github.com/httplib2/httplib2/commit/bd9ee252c8f099608019709e22c0d705e98d26bcPatch, Third Party Advisory
- https://github.com/httplib2/httplib2/pull/182Patch, Third Party Advisory
- https://github.com/httplib2/httplib2/security/advisories/GHSA-93xj-8mrv-444mExploit, Mitigation, Third Party Advisory
- https://pypi.org/project/httplib2Product, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.