Multiple Vendor Network Device Driver Frame Padding Information Disclosure Vulnerability
Network device drivers for several vendors have been reported to disclose potentially sensitive information to attackers.
Frames that are smaller than the minimum frame size should have the unused portion of the frame buffer padded with null (or other) bytes. Some device drivers fail to do this adequately, leaving the data that was stored in the memory comprising the buffer prior to its use intact. Consequently, this data may be transmitted within frames across Ethernet segments. Since the Ethernet frame buffer is allocated in kernel memory space, sensitive data may be leaked.
Cisco has stated that the IOS 12.1 and 12.2 trains are not affected.
National Semiconductor Ethernet controller chips are not vulnerable to this issue.