Improper Handling of Null Character in SSL Certificate Subject Alternative Name Field

CVE-2013-4238 · MEDIUM Severity

AV:N/AC:M/AU:N/C:N/I:P/A:N

The ssl.match_hostname function in the SSL module in Python 2.6 through 3.4 does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408.

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