CVE-2020-3234

What it is

A vulnerability in the virtual console authentication of Cisco IOS Software for Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an authenticated but low-privileged, local attacker to log in to the Virtual Device Server (VDS) of an affected device by using a set of default credentials. The vulnerability is due to the presence of weak, hard-coded credentials. An attacker could exploit this vulnerability by authenticating to the targeted device and then connecting to VDS through the device’s virtual console by using the static credentials. A successful exploit could allow the attacker to access the Linux shell of VDS as the root user.

At a glance

Exploitability

Can be exploited locally on the machine with a low-privilege 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. 2020-06-03 18:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 03:17 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: 8.8 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2020-06-03 18:15 UTC

Last modified

2026-06-17 03:17 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-798 · Hard-coded credentials

Record status

Modified

Affected

• Cisco iOS 12.2\(60\)ez16
• Cisco iOS 15.0\(2\)sg11a
• Cisco iOS 15.3\(3\)jaa1
• Cisco iOS 15.3\(3\)jpj
• Cisco iOS 15.4\(1\)cg
• Cisco iOS 15.4\(2\)cg
• Cisco iOS 15.4\(3\)m
• Cisco iOS 15.4\(3\)m1

Attack profile CVSS 3.1 · 8.8

Attack vector

Local

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Changed

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-2020-3234.md and follow it. Check whether this project is affected by CVE-2020-3234. 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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