cisco-sa-20190807-iosxr-isis-dos-1910: Cisco IOS XR Software Intermediate System-to-Intermediate System Denial of Service Vulnerability

Published Aug 7, 2019
·
Updated

A vulnerability in the implementation of the Intermediate System-to-Intermediate System (IS-IS) routing protocol functionality in Cisco IOS XR Software could allow an unauthenticated attacker who is in the same IS-IS area to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of crafted IS-IS link-state protocol data units (PDUs). An attacker could exploit this vulnerability by sending a crafted link-state PDU to an affected system to be processed. A successful exploit could allow the attacker to cause all routers within the IS-IS area to unexpectedly restart the IS-IS process, resulting in a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-iosxr-isis-dos-1910

Affected Software

1 affected componentFixes available
Cisco IOS XR=6.6.1, <AA15881, =6.5.3, <AA15778
AA15881AA15778

Event History

Aug 7, 2019
Advisory Published
via Cisco·04:00 PM

Child vulnerabilities

Contains the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of cisco-sa-20190807-iosxr-isis-dos-1910?

The severity of cisco-sa-20190807-iosxr-isis-dos-1910 is classified as high due to its potential to cause a Denial of Service (DoS) condition.

2

How do I fix cisco-sa-20190807-iosxr-isis-dos-1910?

To fix cisco-sa-20190807-iosxr-isis-dos-1910, upgrade to a fixed software version of Cisco IOS XR that addresses the vulnerability.

3

Who is affected by cisco-sa-20190807-iosxr-isis-dos-1910?

Organizations using vulnerable versions of Cisco IOS XR Software that implement IS-IS routing protocol are affected by cisco-sa-20190807-iosxr-isis-dos-1910.

4

What versions of Cisco IOS XR are affected by cisco-sa-20190807-iosxr-isis-dos-1910?

Affected versions of Cisco IOS XR include 6.5.3 and 6.6.1 according to cisco-sa-20190807-iosxr-isis-dos-1910.

5

Can exploitation of cisco-sa-20190807-iosxr-isis-dos-1910 be mitigated?

Mitigation of cisco-sa-20190807-iosxr-isis-dos-1910 can be achieved by implementing network segmentation to limit access to vulnerable devices.

Contact

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