CVE-2024-20406

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

Description

A vulnerability in the segment routing feature for the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of ingress IS-IS packets. An attacker could exploit this vulnerability by sending specific IS-IS packets to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the IS-IS process on all affected devices that are participating in the Flexible Algorithm to crash and restart, resulting in a 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. This vulnerability affects segment routing for IS-IS over IPv4 and IPv6 control planes as well as devices that are configured as level 1, level 2, or multi-level routing IS-IS type.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.08%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XR Software
Published at:
Updated at:

References

Link Tags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-isis-xehpbVNe vendor advisory

Frequently Asked Questions

What is the severity of CVE-2024-20406?
CVE-2024-20406 has been scored as a high severity vulnerability.
How to fix CVE-2024-20406?
To fix CVE-2024-20406, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2024-20406 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-20406 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-20406?
CVE-2024-20406 affects Cisco Cisco IOS XR Software.
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