Arch Linux Security Advisory ASA-202102-35 ========================================== Severity: Medium Date : 2021-02-27 CVE-ID : CVE-2021-21240 Package : python-httplib2 Type : denial of service Remote : Yes Link : https://security.archlinux.org/AVG-1546 Summary ======= The package python-httplib2 before version 0.19.0-1 is vulnerable to denial of service. Resolution ========== Upgrade to 0.19.0-1. # pacman -Syu "python-httplib2>=0.19.0-1" The problem has been fixed upstream in version 0.19.0. Workaround ========== The issue can be mitigated by using "httplib2.USE_WWW_AUTH_STRICT_PARSING = True". Description =========== In python-httplib2 before version 0.19.0, a malicious server which responds with a 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. Impact ====== A malicious server can crash the application with crafted HTTP responses. References ========== https://github.com/httplib2/httplib2/security/advisories/GHSA-93xj-8mrv-444m https://github.com/httplib2/httplib2/pull/182 https://github.com/httplib2/httplib2/commit/bd9ee252c8f099608019709e22c0d705... https://security.archlinux.org/CVE-2021-21240