CVE-2025-20115

Cisco IOS XR Software Border Gateway Protocol Denial of Service Vulnerability

Severity
High 8.6
CVSS 3.1
Exploited
Not listed
EPSS
0.009
56.9th percentile
Discovered by
Third party
Published by the vendor
Published
Mar 12, 2025
Assigned by cisco

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.

Weakness: CWE-120

Affected products

Vendor Product Category Matched by
Cisco Cisco IOS XR Software Routing & Switching cna-assigner
Vendor-reported affected versions (1)
  • Cisco · Cisco IOS XR Software