A vulnerability in the implementation of Border Gateway Protocol (BGP) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. The vulnerability is due to incorrect processing of certain BGP update messages. An attacker could exploit this vulnerability by sending BGP update messages that include a specific set of attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic from explicitly defined peers only. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer or would need to be injected by the attacker into the victim’s BGP network on an existing, valid TCP connection to a BGP peer.
asr_9001
CVE-2019-15998
A vulnerability in the access-control logic of the NETCONF over Secure Shell (SSH) of Cisco IOS XR Software may allow connections despite an access control list (ACL) that is configured to deny access to the NETCONF over SSH of an affected device. The vulnerability is due to a missing check in the NETCONF over SSH access control list (ACL). An attacker could exploit this vulnerability by connecting to an affected device using NETCONF over SSH. A successful exploit could allow the attacker to connect to the device on the NETCONF port. Valid credentials are required to access the device. This vulnerability does not affect connections to the default SSH process on the device.