Cisco IOS XR up to 6.6.2 PDU input validation

Summaryinfo

A vulnerability was found in Cisco IOS XR up to 6.6.2. It has been rated as problematic. Affected by this issue is some unknown functionality of the component PDU Handler. This manipulation causes input validation. This vulnerability is tracked as CVE-2019-1910. The attack is only possible within the local network. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Cisco IOS XR up to 6.6.2 (Router Operating System) and classified as problematic. Affected by this vulnerability is an unknown function of the component PDU Handler. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect availability. The summary by CVE is:

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. This vulnerability affects Cisco devices if they are running a vulnerable release of Cisco IOS XR Software earlier than Release 6.6.3 and are configured with the IS–IS routing protocol. Cisco has confirmed that this vulnerability affects both Cisco IOS XR 32-bit Software and Cisco IOS XR 64-bit Software.

The weakness was disclosed 08/07/2019 as cisco-sa-20190807-iosxr-isis-d as confirmed advisory (Website). The advisory is shared at tools.cisco.com. This vulnerability is known as CVE-2019-1910 since 12/06/2018. The attack needs to approached within the local network. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.6.3 eliminates this vulnerability.

The entry VDB-139658 is pretty similar. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• IOS XR

Version

• 6.6.0
• 6.6.1
• 6.6.2

License

• commercial

Website

• Vendor: https://www.cisco.com/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion