A vulnerability in the Link Layer Discovery Protocol (LLDP) feature for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) Mode could allow an unauthenticated, adjacent attacker to cause a memory leak, which could result in an unexpected reload of the device. This vulnerability is due to incorrect error checking when parsing ingress LLDP packets. An attacker could exploit this vulnerability by sending a steady stream of crafted LLDP packets to an affected device. A successful exploit could allow the attacker to cause a memory leak, which could result in a denial of service (DoS) condition when the device unexpectedly reloads. Note: This vulnerability cannot be exploited by transit traffic through the device. The crafted LLDP packet must be targeted to a directly connected interface, and the attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent). In addition, the attack surface for this vulnerability can be reduced by disabling LLDP on interfaces where it is not required.
The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.
The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.
| Link | Tags |
|---|---|
| https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-aci-lldp-dos-ySCNZOpX | vendor advisory mitigation |