A vulnerability in the code of the Cisco ONS 15454 Controller Cards could allow an unauthenticated, remote attacker to prevent system access to the flash memory on the control card.
The vulnerability is caused when the file descriptors are exhausted during a FIN attack. An attacker could exploit this vulnerability by launching a FIN attack at the control card. An exploit could allow the attacker to prevent system write access to the flash memory.
Cisco has confirmed the vulnerability in a security notice and released software updates.
To exploit this vulnerability, an attacker may need access to trusted, internal networks to attempt to conduct a FIN attack at the control card on a targeted device. This access requirement may reduce the possibility of a successful exploit.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.