CVE-2018-0456 Explained : Impact and Mitigation
Learn about CVE-2018-0456, a high-severity vulnerability in Cisco NX-OS Software for Nexus 3000 Series, allowing remote attackers to trigger a denial of service (DoS) by exploiting SNMP input packets.
A vulnerability in Cisco NX-OS Software for Nexus 3000 Series could allow an authenticated, remote attacker to cause a denial of service (DoS) by exploiting the Simple Network Management Protocol (SNMP) input packet processor.
Understanding CVE-2018-0456
This CVE involves a flaw in the processing of SNMP input packets in Cisco NX-OS Software, potentially leading to unexpected restarts of the SNMP application on affected devices.
What is CVE-2018-0456?
The vulnerability stems from inadequate verification of SNMP protocol data units (PDUs) within SNMP packets, enabling an attacker to send customized SNMP packets to trigger multiple restarts of the SNMP application, resulting in a system-level restart and a DoS situation.
The Impact of CVE-2018-0456
- CVSS Base Score: 7.7 (High Severity)
- Attack Vector: Network
- Attack Complexity: Low
- Availability Impact: High
- Privileges Required: Low
- Scope: Changed
- Vector String: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Technical Details of CVE-2018-0456
This section provides detailed technical insights into the vulnerability.
Vulnerability Description
The flaw in the SNMP input packet processor of Cisco NX-OS Software allows an attacker to exploit the SNMP application, causing unexpected restarts and potentially leading to a DoS condition.
Affected Systems and Versions
- Affected Product: Cisco NX-OS Software for Nexus 3000 Series 7.0(3)I7(3)
- Vendor: Cisco
- Affected Version: n/a
Exploitation Mechanism
- The vulnerability can be exploited by sending a crafted SNMP packet to the vulnerable device.
Mitigation and Prevention
Protecting systems from CVE-2018-0456 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Apply vendor-provided patches or updates to mitigate the vulnerability.
- Monitor network traffic for any suspicious SNMP activities.
- Restrict SNMP access to trusted entities only.
Long-Term Security Practices
- Regularly update and patch all software and firmware to address security vulnerabilities.
- Implement network segmentation to limit the impact of potential attacks.
- Conduct regular security assessments and audits to identify and remediate vulnerabilities.
Patching and Updates
- Cisco has likely released patches or updates to address the vulnerability. Ensure timely application of these fixes to secure the affected systems.