Cisco IOS XR Border Gateway Protocol unusual condition

Summaryinfo

A vulnerability identified as problematic has been detected in Cisco IOS XR. The affected element is an unknown function of the component Border Gateway Protocol. The manipulation leads to unusual condition. This vulnerability is documented as CVE-2020-3449. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Cisco IOS XR (Router Operating System) (affected version not known). It has been rated as problematic. This issue affects some unknown functionality of the component Border Gateway Protocol. The manipulation with an unknown input leads to a unusual condition vulnerability. Using CWE to declare the problem leads to CWE-754. The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. Impacted is availability. The summary by CVE is:

A vulnerability in the Border Gateway Protocol (BGP) additional paths feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent authorized users from monitoring the BGP status and cause the BGP process to stop processing new updates, resulting in a denial of service (DOS) condition. The vulnerability is due to an incorrect calculation of lexicographical order when displaying additional path information within Cisco IOS XR Software, which causes an infinite loop. An attacker could exploit this vulnerability by sending a specific BGP update from a BGP neighbor peer session of an affected device; an authorized user must then issue a show bgp command for the vulnerability to be exploited. A successful exploit could allow the attacker to prevent authorized users from properly monitoring the BGP status and prevent BGP from processing new updates, resulting in outdated information in the routing and forwarding tables.

The weakness was released 08/17/2020 as cisco-sa-bgp-ErKEqAer as confirmed advisory (Website). The advisory is shared at tools.cisco.com. The identification of this vulnerability is CVE-2020-3449 since 12/12/2019. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/18/2020).

Upgrading eliminates this vulnerability.

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Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• IOS XR

License

• commercial

Website

• Vendor: https://www.cisco.com/

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

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