Cisco Nexus 9000 Series Fabric Switches ACI Mode Border Leaf Endpoint Learning (CVE-2019-1977)

high Tenable OT Security Plugin ID 501402

Synopsis

The remote OT asset is affected by a vulnerability.

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.

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Solution

Refer to the vendor advisory.

Plugin Details

Severity: High

ID: 501402

Version: 1.1

Type: remote

Family: Tenable.ot

Published: 7/25/2023

Updated: 7/26/2023

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2019-1977

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:cisco:nx-os:12.3%281h%29, cpe:/o:cisco:nx-os:13.1%282m%29, cpe:/o:cisco:nx-os:13.1%282o%29, cpe:/o:cisco:nx-os:13.1%282p%29

Required KB Items: Tenable.ot/Cisco

Exploit Ease: No known exploits are available

Patch Publication Date: 8/30/2019

Vulnerability Publication Date: 8/30/2019

Reference Information

CVE: CVE-2019-1977

CWE: 371

Detections

Analytics