Skip to content
Sign in
CVE-2026-20074Not scored

Cisco IOS XR Software Multi-Instance Intermediate System-to-Intermediate System Denial of Service Vulnerability

Cisco · Cisco IOS XR Software

Not in CISA KEV
0.2%probability of exploitation in the next 30 days
5th percentile
050100

Higher than 5% of scored CVEs

Not scored yet. NVD has not published a CVSS score.

DescriptionNVD

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) multi-instance routing feature of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the IS-IS process to restart unexpectedly. This vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending crafted IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process to restart unexpectedly, resulting in a temporary loss of connectivity to advertised networks and a denial of service (DoS) condition. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and must have formed an adjacency.

Coverage1 article · 1 outlet

First in our coverage: SecurityWeek, 12 Mar.

  1. Cisco Patches High-Severity IOS XR Vulnerabilities
    SecurityWeek · first in our coverage · mentions it in passing

New articles also arrive in the RSS feed.

References

Updated AboutDevelopersSign in