Cisco NX-OS Python Subsystem Parameter access control

Summaryinfo

A vulnerability classified as critical has been found in Cisco NX-OS. This affects an unknown part of the component Python Subsystem. The manipulation as part of Parameter leads to access control. This vulnerability is documented as CVE-2019-1727. The attack needs to be performed locally. There is not any exploit available.

Detailsinfo

A vulnerability was found in Cisco NX-OS (Router Operating System) (version now known). It has been rated as critical. This issue affects some unknown processing of the component Python Subsystem. The manipulation as part of a Parameter leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-264. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the Python scripting subsystem of Cisco NX-OS Software could allow an authenticated, local attacker to escape the Python parser and issue arbitrary commands to elevate the attacker's privilege level. The vulnerability is due to insufficient sanitization of user-supplied parameters that are passed to certain Python functions in the scripting sandbox of the affected device. An attacker could exploit this vulnerability to escape the scripting sandbox and execute arbitrary commands to elevate the attacker's privilege level. To exploit this vulnerability, the attacker must have local access and be authenticated to the targeted device with administrative or Python execution privileges. These requirements could limit the possibility of a successful exploit.

The bug was discovered 05/15/2019. The weakness was released 05/15/2019 as cisco-sa-20190515-nxos-pyth-es as confirmed advisory (Website). It is possible to read the advisory at tools.cisco.com. The identification of this vulnerability is CVE-2019-1727 since 12/06/2018. Attacking locally is a requirement. Required for exploitation is a simple authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/19/2023). The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 316465 (Cisco NX-OS Software Python Parser Privilege Escalation Vulnerability(cisco-sa-20190515-nxos-pyth-escal)).

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

Entries connected to this vulnerability are available at VDB-135075, VDB-135074, VDB-135073 and VDB-135070. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• NX-OS

License

• commercial

Website

• Vendor: https://www.cisco.com/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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