CVE-2013-2099
python: ssl.match_hostname() DoS via certificates with specially crafted hostname wildcard patterns
Severity
LowRed Hat Product Security
CVSS 2.0
Review impact separately from score.
Published · May 15, 2013
Updated · June 28, 2026
Description
A denial of service flaw was found in the way Python's SSL module implementation performed matching of certain certificate names. A remote attacker able to obtain a valid certificate that contained multiple wildcard characters could use this flaw to issue a request to validate such a certificate, resulting in excessive consumption of CPU.
Statement
This issue did not affect the versions of python as shipped with Red Hat Enterprise Linux 5 and 6 as the SSL module there did not implement the match_hostname() routine yet.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 2.0 · 2.6AV:N/AC:H/Au:N/C:N/I:N/A:P
CWE-407 · Inefficient Algorithmic Complexity