CVE-2013-7459

This is a security fix for a possible Buffer overflow. AES.new with invalid parameter crashes python. The IV parameter is currently ignored when initializing a cipher in ECB or CTR mode. There was a bug in pycrypto which could be exploited to get a shell.

Heap-based buffer overflow in the ALGnew function in block_templace.c in Python Cryptography Toolkit (aka pycrypto) allows remote attackers to execute arbitrary code as demonstrated by a crafted iv parameter to cryptmsg.py.

This update for python-pycrypto fixes the following issues:

• CVE-2013-7459: Fixed a potential heap buffer overflow in ALGnew (bsc#1017420).

This update for python-pycrypto fixes the following issues:

• CVE-2013-7459: Fixed a potential heap buffer overflow in ALGnew (bsc#1017420).

python-paramiko was adjusted to work together with this python-pycrypto change. (bsc#1047666)

It was discovered that the ALGnew function in block_templace.c in the Python Cryptography Toolkit contained a heap-based buffer overflow vulnerability. A remote attacker could use this flaw to execute arbitrary code by using a crafted initialization vector parameter.

USN-3199-1 fixed a vulnerability in the Python Cryptography Toolkit. Unfortunately, various programs depended on the original behavior of the Python Cryptography Toolkit which was altered when fixing the vulnerability. This update retains the fix for the vulnerability but issues a warning rather than throwing an exception. Code which produces this warning should be updated because future versions of the Python Cryptography Toolkit re-introduce the exception.

We apologize for the inconvenience.

Original advisory details:

It was discovered that the ALGnew function in block_template.c in the Python Cryptography Toolkit contained a heap-based buffer overflow vulnerability. A remote attacker could use this flaw to execute arbitrary code by using a crafted initialization vector parameter.