CVE-2018-0295 : What You Need to Know

A weakness has been identified in the Border Gateway Protocol (BGP) implementation of Cisco NX-OS Software that can potentially allow a remote attacker to cause a denial of service (DoS) situation by causing the device to unexpectedly reload.

Understanding CVE-2018-0295

This CVE involves a vulnerability in the BGP implementation of Cisco NX-OS Software that could lead to a DoS condition.

What is CVE-2018-0295?

The vulnerability stems from inadequate validation of input for BGP update messages, allowing an unauthenticated attacker to trigger a DoS by sending a carefully crafted BGP update message.

The Impact of CVE-2018-0295

Remote unauthenticated attackers can exploit the vulnerability to force a device reload, causing a DoS situation.
The attacker needs to send a malicious BGP update message to the device to execute the exploit.
Affected systems include various Nexus Series Switches operating in different modes.

Technical Details of CVE-2018-0295

This section provides detailed technical insights into the vulnerability.

Vulnerability Description

Inadequate validation of input for BGP update messages in Cisco NX-OS Software.
Attackers can exploit this by sending carefully crafted BGP messages to trigger unexpected reloads.

Affected Systems and Versions

Nexus 2000, 3000, 3500, 3600, 5500, 5600, 6000, 7000, 7700, and 9000 Series Switches.
Includes Nexus 9000 Series Fabric Switches in ACI mode and standalone NX-OS mode.

Exploitation Mechanism

Attackers must send malicious packets over a TCP connection appearing to be from a trusted BGP peer.
They can introduce malformed messages into the victim's BGP network, requiring knowledge of BGP peers.

Mitigation and Prevention

Steps to address and prevent exploitation of CVE-2018-0295.

Immediate Steps to Take

Apply vendor-supplied patches and updates promptly.
Implement network segmentation to limit the impact of potential attacks.
Monitor BGP traffic for anomalies and unauthorized activities.

Long-Term Security Practices

Regularly review and update BGP configurations and access control lists.
Conduct security awareness training to educate staff on BGP security best practices.

Patching and Updates

Cisco has released patches addressing the vulnerability.
Regularly check for updates and apply them to ensure system security.