Vulnerability Description
Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerabilities are due to incorrect processing of BGP update messages that contain crafted EVPN attributes. An attacker could exploit these vulnerabilities by sending BGP EVPN update messages with malformed attributes to be processed by an affected system. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit these vulnerabilities, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Ios Xr | 6.6.1 |
| Cisco | Asr 9000V | - |
| Cisco | Asr 9001 | - |
| Cisco | Asr 9006 | - |
| Cisco | Asr 9010 | - |
| Cisco | Asr 9901 | - |
| Cisco | Asr 9904 | - |
| Cisco | Asr 9906 | - |
| Cisco | Asr 9910 | - |
| Cisco | Asr 9912 | - |
| Cisco | Asr 9922 | - |
| Cisco | Ncs 540 | - |
| Cisco | Ncs 5501 | - |
| Cisco | Ncs 5501-Se | - |
| Cisco | Ncs 5502 | - |
| Cisco | Ncs 5502-Se | - |
| Cisco | Ncs 5508 | - |
| Cisco | Ncs 5516 | - |
| Cisco | Ncs 6000 | - |
| Cisco | Crs | - |
Related Weaknesses (CWE)
References
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-2Vendor Advisory
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-2Vendor Advisory
FAQ
What is CVE-2019-16020?
CVE-2019-16020 is a vulnerability with a CVSS score of 8.6 (HIGH). Multiple vulnerabilities in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a de...
How severe is CVE-2019-16020?
CVE-2019-16020 has been rated HIGH with a CVSS base score of 8.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2019-16020?
Check the references section above for vendor advisories and patch information. Affected products include: Cisco Ios Xr, Cisco Asr 9000V, Cisco Asr 9001, Cisco Asr 9006, Cisco Asr 9010.