CVE-2018-0395 : What You Need to Know
Learn about CVE-2018-0395, a high-severity vulnerability in Cisco FXOS and NX-OS Software allowing DoS attacks. Find mitigation steps and patching details here.
A weakness in the Link Layer Discovery Protocol (LLDP) implementation in Cisco FXOS Software and Cisco NX-OS Software could lead to a denial of service (DoS) attack. This vulnerability arises from inadequate validation of specific TLV fields within the LLDP frame header.
Understanding CVE-2018-0395
This CVE identifies a vulnerability in Cisco FXOS Software and Cisco NX-OS Software that could be exploited by an unauthenticated attacker in close proximity to cause a DoS situation.
What is CVE-2018-0395?
The vulnerability in the LLDP implementation allows an attacker to send a specially crafted LLDP packet to a device, triggering an unexpected reload and potential DoS.
The Impact of CVE-2018-0395
- CVSS Base Score: 8.8 (High Severity)
- Attack Vector: Adjacent Network
- Confidentiality Impact: High
- Integrity Impact: High
- Availability Impact: High
Technical Details of CVE-2018-0395
This section delves into the specifics of the vulnerability.
Vulnerability Description
The vulnerability stems from inadequate validation of TLV fields within the LLDP frame header, enabling an attacker to exploit this flaw by sending a crafted LLDP packet.
Affected Systems and Versions
- Cisco NX-OS Software: Versions less than 6.2(1)
- Firepower 4100 Series Next-Generation Firewalls: Versions less than 2.3.1.58
Exploitation Mechanism
The attacker needs to send a specially crafted LLDP packet to a device's interface to trigger the vulnerability, potentially causing the device to reload unexpectedly.
Mitigation and Prevention
Protecting systems from CVE-2018-0395 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Apply vendor-released patches or updates promptly.
- Monitor network traffic for any signs of exploitation.
- Implement network segmentation to limit the impact of potential attacks.
Long-Term Security Practices
- Regularly update and patch all software and firmware.
- Conduct security training to educate users on identifying and reporting suspicious activities.
Patching and Updates
- Cisco has released patches to address this vulnerability. Ensure all affected systems are updated with the latest security fixes.