CVE-2017-6791 Explained : Impact and Mitigation

A flaw in the Trust Verification Service (TVS) of Cisco Unified Communications Manager could allow remote attackers to cause a denial of service (DoS) situation. This CVE was published on September 7, 2017.

Understanding CVE-2017-6791

This CVE identifies a vulnerability in the TVS of Cisco Unified Communications Manager that could lead to a DoS condition on affected devices.

What is CVE-2017-6791?

The vulnerability stems from the mishandling of Transport Layer Security (TLS) traffic by the affected software, enabling attackers to disrupt TVS access, resulting in a persistent DoS situation until service restart.

The Impact of CVE-2017-6791

Unauthorized individuals can exploit the flaw remotely to cause a DoS situation on impacted devices.
Attackers can obstruct access to TVS, leading to service disruption until manual intervention.

Technical Details of CVE-2017-6791

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The flaw in the TVS of Cisco Unified Communications Manager allows attackers to generate incomplete traffic streams, disrupting TVS access and causing a DoS condition.

Affected Systems and Versions

Cisco Unified Communications Manager versions 10.0(1.10000.24), 10.5(2.10000.5), 11.0(1.10000.10), and 9.1(2.10000.28) are identified as affected.

Exploitation Mechanism

Attackers exploit the vulnerability by generating incomplete traffic streams, denying access to TVS and causing a DoS condition.

Mitigation and Prevention

Protecting systems from CVE-2017-6791 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply vendor-provided patches promptly to mitigate the vulnerability.
Monitor network traffic for any signs of exploitation.

Long-Term Security Practices

Regularly update and patch software to prevent known vulnerabilities.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Stay informed about security advisories and updates from Cisco.
Regularly check for patches and apply them to ensure system security.