Debian Linux Security Advisory 2763-1 - It was discovered that PyOpenSSL, a Python wrapper around the OpenSSL library, does not properly handle certificates with NULL characters in the Subject Alternative Name field.
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Ubuntu Security Notice 1965-1 - It was discovered that pyOpenSSL did not properly handle certificates with NULL characters in the Subject Alternative Name field. An attacker could exploit this to perform a man in the middle attack to view sensitive information or alter encrypted communications.
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Mandriva Linux Security Advisory 2013-233 - The string formatting of subjectAltName X509Extension instances in pyOpenSSL before 0.13.1 incorrectly truncated fields of the name when encountering a null byte, possibly allowing man-in-the-middle attacks through certificate spoofing. The updated packages have been patched to correct this issue.
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