CVE-2023-20040

What it is

A vulnerability in the NETCONF service of Cisco Network Services Orchestrator (NSO) could allow an authenticated, remote attacker to cause a denial of service (DoS) on an affected system that is running as the root user. To exploit this vulnerability, the attacker must be a member of the admin group. This vulnerability exists because user-supplied input is not properly validated when NETCONF is used to upload packages to an affected device. An attacker could exploit this vulnerability by uploading a specially crafted package file. A successful exploit could allow the attacker to write crafted files to arbitrary locations on the filesystem or delete arbitrary files from the filesystem of an affected device, resulting in a DoS condition. Note: By default, during install, Cisco NSO will be set up to run as the root user unless the --run-as-user option is used.

At a glance

Exploitability

Can be exploited over the network with an admin-level account. High risk of service disruption.

Exploit odds

1.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2023-01-20 07:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 05:29 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 1.3% in the next 30 days (EPSS).
• Severity: 5.5 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2023-01-20 07:15 UTC

Last modified

2026-06-17 05:29 UTC

Exploit probability

1.3% · EPSS, next 30 days

Weakness

CWE-23

Record status

Modified

Affected

• Cisco Network Services Orchestrator < 5.4.7
• Cisco Network Services Orchestrator < 5.5.6
• Cisco Network Services Orchestrator < 5.6.7
• Cisco Network Services Orchestrator < 5.7.4
• Cisco Network Services Orchestrator 5.8

Attack profile CVSS 3.1 · 5.5

Attack vector

Network

Complexity

Low

Privileges needed

High

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2023-20040.md and follow it. Check whether this project is affected by CVE-2023-20040. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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