CVE-2020-24355 : What You Need to Know

Zyxel VMG5313-B30B router on firmware 5.13(ABCJ.6)b3_1127, and possibly older versions of firmware are affected by insecure permissions allowing users to create new users with elevated privileges.

Understanding CVE-2020-24355

This CVE identifies a security vulnerability in Zyxel VMG5313-B30B routers that enables users to manipulate JSON data during account creation to gain elevated privileges.

What is CVE-2020-24355?

The vulnerability in Zyxel VMG5313-B30B routers allows regular and other users to create new users with elevated privileges by modifying the "FirstIndex" field in the JSON data during account creation.

The Impact of CVE-2020-24355

The insecure permissions in affected firmware versions can lead to unauthorized users gaining elevated privileges, posing a significant security risk to the network and data.

Technical Details of CVE-2020-24355

Zyxel VMG5313-B30B router on firmware 5.13(ABCJ.6)b3_1127, and possibly older versions of firmware are affected by this vulnerability.

Vulnerability Description

The vulnerability allows users to create new accounts with elevated privileges by manipulating JSON data during account creation.

Affected Systems and Versions

Zyxel VMG5313-B30B router on firmware 5.13(ABCJ.6)b3_1127
Possibly older versions of firmware

Exploitation Mechanism

Users exploit the vulnerability by changing the "FirstIndex" field in the JSON data during account creation, granting themselves elevated privileges.

Mitigation and Prevention

It is crucial to take immediate steps to mitigate the risks posed by CVE-2020-24355.

Immediate Steps to Take

Update the router firmware to the latest version provided by Zyxel.
Monitor user accounts for any unauthorized changes.
Restrict access to the router's administration interface.

Long-Term Security Practices

Regularly review and update router firmware to address security vulnerabilities.
Educate users on secure password practices and the importance of account security.

Patching and Updates

Apply patches and updates released by Zyxel promptly to address the vulnerability and enhance the security of the router.