Cisco NX-OS Border Gateway Protocol TCP Connection input validation

Summaryinfo

A vulnerability was found in Cisco NX-OS and classified as problematic. Affected by this vulnerability is an unknown functionality of the component Border Gateway Protocol. Executing a manipulation as part of TCP Connection can lead to input validation. This vulnerability is handled as CVE-2018-0295. The attack can be executed remotely. There is not any exploit available. The application of restrictive firewalling is recommended.

Detailsinfo

A vulnerability classified as problematic was found in Cisco NX-OS (Router Operating System) (the affected version is unknown). This vulnerability affects an unknown code of the component Border Gateway Protocol. The manipulation as part of a TCP Connection 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. CVE summarizes:

A vulnerability in the Border Gateway Protocol (BGP) implementation of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition due to the device unexpectedly reloading. The vulnerability is due to incomplete input validation of the BGP update messages. An attacker could exploit this vulnerability by sending a crafted BGP update message to the targeted device. An exploit could allow the attacker to cause the switch to reload unexpectedly. The Cisco implementation of the BGP protocol only accepts incoming BGP traffic from explicitly defined peers. To exploit this vulnerability, an attacker must be able to send the malicious packets over a TCP connection that appears to come from a trusted BGP peer or inject malformed messages into the victim's BGP network. This would require obtaining information about the BGP peers in the affected system's trusted network. The vulnerability may be triggered when the router receives a malformed BGP message from a peer on an existing BGP session. At least one BGP neighbor session must be established for a router to be vulnerable. This vulnerability affects Nexus 2000 Series Switches, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 3600 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules. Cisco Bug IDs: CSCve79599, CSCve87784, CSCve91371, CSCve91387.

The bug was discovered 06/20/2018. The weakness was released 06/20/2018 as cisco-sa-20180620-nxosbgp / CSCve91387 as confirmed advisory (Website). The advisory is available at tools.cisco.com. This vulnerability was named CVE-2018-0295 since 11/27/2017. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 03/28/2023).

The commercial vulnerability scanner Qualys is able to test this issue with plugin 316289 (Cisco NX-OS Software Border Gateway Protocol Denial of Service Vulnerability(cisco-sa-20180620-nxosbgp)).

Proper firewalling of is able to address this issue.

Entries connected to this vulnerability are available at VDB-119749, VDB-119747, VDB-119743 and VDB-119744. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• NX-OS

License

• commercial

Website

• Vendor: https://www.cisco.com/

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CPE 2.2info

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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