CVE-2020-3408 : Security Advisory and Response
Learn about CVE-2020-3408, a vulnerability in Cisco IOS and IOS XE Software that allows remote attackers to cause a denial of service condition by forcing device reloads. Find out the impact, affected systems, exploitation details, and mitigation steps.
A vulnerability in the Split DNS feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition by forcing an affected device to reload.
Understanding CVE-2020-3408
This CVE involves a vulnerability in Cisco IOS and IOS XE Software that could lead to a DoS attack.
What is CVE-2020-3408?
The vulnerability in the Split DNS feature of Cisco IOS and IOS XE Software allows a remote attacker to trigger a device reload, resulting in a DoS condition.
The Impact of CVE-2020-3408
- Attack Complexity: Low
- Attack Vector: Network
- Availability Impact: High
- Base Score: 8.6 (High Severity)
- No impact on Confidentiality or Integrity
- No privileges required
- User Interaction: None
- Scope: Changed
Technical Details of CVE-2020-3408
This section provides detailed technical information about the vulnerability.
Vulnerability Description
The vulnerability occurs due to a timeout in the regular expression engine used with the Split DNS feature, leading to a device reload when processing DNS name list configurations.
Affected Systems and Versions
- Product: Cisco IOS
- Vendor: Cisco
- Affected Version: n/a
Exploitation Mechanism
An attacker can exploit this vulnerability by attempting to resolve an address or hostname handled by the affected device, causing it to reload and resulting in a DoS condition.
Mitigation and Prevention
Steps to address and prevent exploitation of CVE-2020-3408.
Immediate Steps to Take
- Apply vendor patches and updates promptly.
- Implement network segmentation to limit the impact of potential attacks.
- Monitor network traffic for any suspicious activity.
Long-Term Security Practices
- Regularly update and patch all software and firmware.
- Conduct security assessments and penetration testing.
- Educate users and IT staff on security best practices.
Patching and Updates
- Cisco has released patches to address this vulnerability. Ensure all affected systems are updated with the latest security fixes.