CVE-2020-3479 : Exploit Details and Defense Strategies
Learn about CVE-2020-3479, a vulnerability in Cisco IOS and IOS XE Software that allows remote attackers to cause a denial of service condition. Find out the impact, affected systems, and mitigation steps.
A vulnerability in the implementation of Multiprotocol Border Gateway Protocol (MP-BGP) for the Layer 2 VPN (L2VPN) Ethernet VPN (EVPN) address family in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition.
Understanding CVE-2020-3479
This CVE involves a vulnerability in Cisco IOS and IOS XE Software that could lead to a denial of service attack.
What is CVE-2020-3479?
The vulnerability in the implementation of MP-BGP for L2VPN EVPN in Cisco IOS and IOS XE Software allows a remote attacker to trigger a DoS condition by sending crafted BGP update messages.
The Impact of CVE-2020-3479
The vulnerability could result in a DoS condition, causing affected devices to crash, disrupting services and potentially leading to downtime.
Technical Details of CVE-2020-3479
This section provides more technical insights into the vulnerability.
Vulnerability Description
The vulnerability arises from incorrect processing of BGP update messages containing specific EVPN attributes, allowing attackers to crash affected devices.
Affected Systems and Versions
- Product: Cisco IOS 15.2(5)E1
- Vendor: Cisco
- Version: n/a
Exploitation Mechanism
Attackers can exploit this vulnerability by sending BGP update messages with malformed attributes to the target device, triggering a crash and causing a DoS condition.
Mitigation and Prevention
Protecting systems from this vulnerability 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 BGP update messages.
Long-Term Security Practices
- Regularly update and patch software to address known vulnerabilities.
- Implement network segmentation and access controls to limit the impact of potential attacks.
Patching and Updates
Regularly check for security advisories from Cisco and apply patches promptly to ensure system security.