CVE-2021-21894 : Exploit Details and Defense Strategies

A directory traversal vulnerability in Lantronix PremierWave 2050 8.9.0.0R4 can allow an attacker to overwrite or disclose arbitrary files through a specially crafted HTTP request.

Understanding CVE-2021-21894

This CVE identifies a critical directory traversal vulnerability in Lantronix PremierWave 2050 8.9.0.0R4.

What is CVE-2021-21894?

CVE-2021-21894 refers to a security flaw in the Web Manager FsTFtp functionality of Lantronix PremierWave 2050 8.9.0.0R4 (in QEMU). An attacker with high privileges can exploit this vulnerability to manipulate files via HTTP requests.

The Impact of CVE-2021-21894

The severity score for this CVE is 9.1 (Critical) based on CVSS v3.0 metrics. It poses a high risk to confidentiality, integrity, and availability of affected systems.

Technical Details of CVE-2021-21894

This section delves into the specifics of the vulnerability.

Vulnerability Description

A directory traversal vulnerability in Lantronix PremierWave 2050 8.9.0.0R4 enables attackers to overwrite or disclose files using crafted HTTP requests.

Affected Systems and Versions

The vulnerability affects Lantronix PremierWave 2050 8.9.0.0R4 running in the QEMU environment.

Exploitation Mechanism

By sending specially crafted HTTP requests to the Web Manager FsTFtp functionality, attackers can trigger unauthorized file operations.

Mitigation and Prevention

Discover how to secure your systems against CVE-2021-21894.

Immediate Steps to Take

Implement access controls, update software, and monitor HTTP traffic to mitigate immediate risks.

Long-Term Security Practices

Enforce the principle of least privilege, conduct regular security audits, and educate users on safe browsing habits.

Patching and Updates

Apply patches from Lantronix promptly to address this critical vulnerability.