CVE-2019-1967 : Vulnerability Insights and Analysis
Learn about CVE-2019-1967 affecting Cisco NX-OS Software. Discover the impact, affected versions, and mitigation steps to prevent NTP DoS attacks on vulnerable devices.
An unauthenticated, remote attacker could potentially cause a denial of service (DoS) situation on a vulnerable device through a vulnerability discovered in the Network Time Protocol (NTP) feature of Cisco NX-OS Software.
Understanding CVE-2019-1967
This CVE involves a vulnerability in the NTP feature of Cisco NX-OS Software that could lead to a DoS condition on affected devices.
What is CVE-2019-1967?
The vulnerability arises from excessive resource utilization when the device logs a drop action for received Mode 7 NTP packets, allowing an attacker to flood the device with such packets, inducing high CPU and memory usage.
The Impact of CVE-2019-1967
- CVSS Base Score: 8.6 (High)
- Attack Vector: Network
- Availability Impact: High
- Successful exploitation could lead to system processes restart or unexpected device reload.
Technical Details of CVE-2019-1967
This section provides more technical insights into the vulnerability.
Vulnerability Description
The vulnerability in the NTP feature of Cisco NX-OS Software allows for a DoS attack by flooding the device with Mode 7 NTP packets.
Affected Systems and Versions
- Affected Product: Cisco NX-OS Software
- Vendor: Cisco
- Affected Versions: Less than 8.3(2) (unspecified)
Exploitation Mechanism
- Attacker floods the device with Mode 7 NTP packets
- Excessive CPU and memory usage induced
Mitigation and Prevention
Protecting systems from CVE-2019-1967 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Disable NTP feature if not essential
- Implement access control lists to restrict NTP traffic
- Monitor and analyze NTP traffic for anomalies
Long-Term Security Practices
- Regularly update and patch Cisco NX-OS Software
- Conduct security assessments and audits periodically
- Stay informed about security advisories and best practices
- Implement network segmentation to contain potential attacks
Patching and Updates
- Apply patches provided by Cisco to address the vulnerability
- Keep systems up to date with the latest security fixes