CVE-2020-3436 Explained : Impact and Mitigation

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to upload arbitrary-sized files to specific folders on an affected device, leading to an unexpected device reload.

Understanding CVE-2020-3436

This CVE involves a denial of service vulnerability in Cisco ASA and FTD Software due to inefficient handling of large file uploads.

What is CVE-2020-3436?

The vulnerability allows attackers to upload files to specific folders, triggering a watchdog timeout and causing the device to reload unexpectedly, resulting in a denial of service condition.

The Impact of CVE-2020-3436

CVSS Base Score: 8.6 (High Severity)
Attack Vector: Network
Availability Impact: High
The vulnerability could lead to a denial of service condition by causing devices to reload unexpectedly.

Technical Details of CVE-2020-3436

This section provides more technical insights into the vulnerability.

Vulnerability Description

The affected software does not efficiently handle the writing of large files to specific folders on the local file system, allowing attackers to trigger device reloads.

Affected Systems and Versions

Affected Product: Cisco Adaptive Security Appliance (ASA) Software
Vendor: Cisco
Affected Version: Not Applicable

Exploitation Mechanism

Attackers can exploit this vulnerability by uploading files to specific folders, causing a watchdog timeout and device reload.

Mitigation and Prevention

Protecting systems from CVE-2020-3436 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply vendor-provided patches or updates promptly.
Monitor network traffic for any suspicious activities.
Restrict access to vulnerable systems.

Long-Term Security Practices

Regularly update and patch software to address known vulnerabilities.
Implement network segmentation to limit the impact of potential attacks.
Conduct security training for employees to recognize and report suspicious activities.

Patching and Updates

Cisco has likely released patches or updates to address this vulnerability. Ensure timely installation to mitigate the risk of exploitation.