Cisco NX-OS Software Remote Management Memory Leak Denial of Service (CVE-2019-1965)

high Tenable OT Security Plugin ID 501296

Synopsis

The remote OT asset is affected by a vulnerability.

Description

A vulnerability in the Virtual Shell (VSH) session management for Cisco NX-OS Software could allow an authenticated, remote attacker to cause a VSH process to fail to delete upon termination. This can lead to a build-up of VSH processes that overtime can deplete system memory. When there is no system memory available, this can cause unexpected system behaviors and crashes. The vulnerability is due to the VSH process not being properly deleted when a remote management connection to the device is disconnected. An attacker could exploit this vulnerability by repeatedly performing a remote management connection to the device and terminating the connection in an unexpected manner. A successful exploit could allow the attacker to cause the VSH processes to fail to delete, which can lead to a system- wide denial of service (DoS) condition. The attacker must have valid user credentials to log in to the device using the remote management connection.

This plugin only works with Tenable.ot.
Please visit https://www.tenable.com/products/tenable-ot for more information.

Solution

Refer to the vendor advisory.

Plugin Details

Severity: High

ID: 501296

Version: 1.2

Type: remote

Family: Tenable.ot

Published: 7/25/2023

Updated: 10/16/2025

Supported Sensors: Tenable OT Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 4

Temporal Score: 3

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

CVSS Score Source: CVE-2019-1965

CVSS v3

Risk Factor: High

Base Score: 7.7

Temporal Score: 6.7

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

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

Vulnerability Information

CPE: cpe:/o:cisco:nexus_7000_series_switches, cpe:/o:cisco:nexus_5000_series_switches, cpe:/o:cisco:nexus_3000_series_switches, cpe:/o:cisco:nexus_9000_series_switches, cpe:/o:cisco:nexus_6000_series_switches

Required KB Items: Tenable.ot/Cisco

Exploit Ease: No known exploits are available

Patch Publication Date: 8/28/2019

Vulnerability Publication Date: 8/28/2019

Reference Information

CVE: CVE-2019-1965

CWE: 772

Detections

Analytics