Cisco Internetwork Operating System (IOS) may allow a heap-based buffer overflow vulnerability to execute arbitrary code after bypassing heap integrity checks.
Cisco IOS contains functionality for checking the integrity of the heap, which is a specific region in memory where data is stored. This additional checking ensures that an attacker has not modified the heap through a heap-based buffer overflow vulnerability or other methods.
Nominally, heap integrity checking will force the device to reload if the integrity checks fail. This intended behavior may have the side effect of a temporary denial-of-service condition while the device resets. However, certain conditions have been discovered that may allow an attacker to achieve arbitrary code execution without crashing or resetting the device immediately. In some cases, this may be achieved by overwriting special areas of system memory. The overwritten system memory is then executed in place of the intended system code, resulting in the attacker gaining full control of the device.
An attacker may escalate the impact of another vulnerability in order to take control of the device or execute arbitrary code.
Apply an update
Thanks to the Cisco Systems Product Security Incident Response Team for reporting this vulnerability.
This document was written by Ken MacInnis.
|Date First Published:||2005-11-03|
|Date Last Updated:||2005-11-03 18:24 UTC|