Cisco Small Business Switches Secure Shell improper authorization

Summaryinfo

A vulnerability marked as critical has been reported in Cisco Small Business Switches. This issue affects some unknown processing of the component Secure Shell. The manipulation leads to improper authorization. This vulnerability is traded as CVE-2019-1859. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Cisco Small Business Switches (the affected version is unknown). It has been rated as critical. This issue affects an unknown code of the component Secure Shell. The manipulation with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the Secure Shell (SSH) authentication process of Cisco Small Business Switches software could allow an attacker to bypass client-side certificate authentication and revert to password authentication. The vulnerability exists because OpenSSH mishandles the authentication process. An attacker could exploit this vulnerability by attempting to connect to the device via SSH. A successful exploit could allow the attacker to access the configuration as an administrative user if the default credentials are not changed. There are no workarounds available; however, if client-side certificate authentication is enabled, disable it and use strong password authentication. Client-side certificate authentication is disabled by default.

The bug was discovered 05/01/2019. The weakness was shared 05/03/2019 as cisco-sa-20190501-scbv as confirmed advisory (Website). The advisory is shared at tools.cisco.com. The identification of this vulnerability is CVE-2019-1859 since 12/06/2018. The attack may be initiated remotely. A simple authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/12/2023). MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $5k-$25k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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

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Vendor

• Cisco

Name

• Small Business Switches

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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