SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2019-1977

A vulnerability within the Endpoint Learning feature of Cisco Nexus 9000 Series Switches running in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an endpoint…

HIGH 7.5EPSS 1.49%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.49%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability within the Endpoint Learning feature of Cisco Nexus 9000 Series Switches running in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an endpoint device in certain circumstances. The vulnerability is due to improper endpoint learning when packets are received on a specific port from outside the ACI fabric and destined to an endpoint located on a border leaf when Disable Remote Endpoint Learning has been enabled. This can result in a Remote (XR) entry being created for the impacted endpoint that will become stale if the endpoint migrates to a different port or leaf switch. This results in traffic not reaching the impacted endpoint until the Remote entry can be relearned by another mechanism.

CVSS 3.0
7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
1.49% probability · 73th percentile
CISA KEV
Not listed
Weakness
CWE-371
Affected
cisco/nx-os
Source
psirt@cisco.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.