CVE-2017-3827 : Vulnerability Insights and Analysis

A vulnerability in the Multipurpose Internet Mail Extensions (MIME) scanner of Cisco AsyncOS Software for Cisco Email Security Appliances (ESA) and Web Security Appliances (WSA) could allow an unauthenticated, remote attacker to bypass configured user filters on the device. This CVE affects all versions of Cisco AsyncOS Software for Cisco ESA and Cisco WSA, including virtual and hardware appliances, that have message or content filters set up to scan incoming email attachments on the ESA or services scanning content of web access on the WSA.

Understanding CVE-2017-3827

This CVE, published on February 22, 2017, poses a risk to Cisco Email Security Appliances (ESA) and Web Security Appliances (WSA) utilizing Cisco AsyncOS Software.

What is CVE-2017-3827?

The vulnerability in the MIME scanner of Cisco AsyncOS Software for Cisco ESA and WSA allows unauthorized attackers to bypass user filters configured on the devices.

The Impact of CVE-2017-3827

Unauthorized attackers can circumvent user filters on affected devices.

Technical Details of CVE-2017-3827

This section provides detailed technical information about the CVE.

Vulnerability Description

The flaw in the MIME scanner of Cisco AsyncOS Software for Cisco ESA and WSA enables attackers to bypass configured user filters on the devices.

Affected Systems and Versions

All versions of Cisco AsyncOS Software for Cisco ESA and Cisco WSA are impacted, including virtual and hardware appliances.
Affected releases include 10.0.0-203, 9.9.9-894 for WSA, and WSA10.0.0-233.

Exploitation Mechanism

Attackers can exploit this vulnerability to evade user filters configured on Cisco ESA and WSA devices.

Mitigation and Prevention

Protecting systems from CVE-2017-3827 is crucial to maintaining security.

Immediate Steps to Take

Apply patches provided by Cisco to fix the vulnerability.
Review and update filter configurations to enhance security.

Long-Term Security Practices

Regularly monitor and update security configurations on Cisco ESA and WSA devices.
Conduct security assessments to identify and address potential vulnerabilities.

Patching and Updates

Install the latest updates and patches released by Cisco to address the filtering bypass vulnerability.