CVE-2021-34726

What it is

A vulnerability in the CLI of Cisco SD-WAN Software could allow an authenticated, local attacker to inject arbitrary commands to be executed with root-level privileges on the underlying operating system of an affected device. This vulnerability is due to insufficient input validation on certain CLI commands. An attacker could exploit this vulnerability by authenticating to an affected device and submitting crafted input to the CLI. The attacker must be authenticated as an administrative user to execute the affected commands. A successful exploit could allow the attacker to execute commands with root-level privileges.

At a glance

Exploitability

Can be exploited locally on the machine with an admin-level account. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

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

Timeline

1. 2021-09-23 03:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 03:56 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.4% in the next 30 days (EPSS).
• Severity: 6.7 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2021-09-23 03:15 UTC

Last modified

2026-06-17 03:56 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-77 · Command injection

Record status

Modified

Affected

• Cisco sd-wan < 18.4.6
• Cisco sd-wan < 19.2.3
• Cisco sd-wan < 20.1.2
• Cisco sd-wan < 20.3.1
• Cisco sd-wan < 20.4.1
• Cisco sd-wan < 20.5.1

Attack profile CVSS 3.1 · 6.7

Attack vector

Local

Complexity

Low

Privileges needed

High

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

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-2021-34726.md and follow it. Check whether this project is affected by CVE-2021-34726. 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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