Vulnerability Description
A vulnerability in confederation implementation for the Border Gateway Protocol (BGP) in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to a memory corruption that occurs when a BGP update is created with an AS_CONFED_SEQUENCE attribute that has 255 autonomous system numbers (AS numbers). An attacker could exploit this vulnerability by sending a crafted BGP update message, or the network could be designed in such a manner that the AS_CONFED_SEQUENCE attribute grows to 255 AS numbers or more. A successful exploit could allow the attacker to cause memory corruption, which may cause the BGP process to restart, resulting in a DoS condition. To exploit this vulnerability, an attacker must control a BGP confederation speaker within the same autonomous system as the victim, or the network must be designed in such a manner that the AS_CONFED_SEQUENCE attribute grows to 255 AS numbers or more.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Ios Xr | 6.5.1 |
Related Weaknesses (CWE)
References
- https://blog.apnic.net/2024/09/02/crafting-endless-as-paths-in-bgp/Third Party Advisory
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/ciVendor Advisory
FAQ
What is CVE-2025-20115?
CVE-2025-20115 is a vulnerability with a CVSS score of 8.6 (HIGH). A vulnerability in confederation implementation for the Border Gateway Protocol (BGP) in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) c...
How severe is CVE-2025-20115?
CVE-2025-20115 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-2025-20115?
Check the references section above for vendor advisories and patch information. Affected products include: Cisco Ios Xr.