Cisco Identity Services Engine 3.3.0/3.4.0/3.5.0 IPsec Open API injection

Summaryinfo

A vulnerability categorized as problematic has been discovered in Cisco Identity Services Engine 3.3.0/3.4.0/3.5.0. This issue affects some unknown processing of the component IPsec Open API. Such manipulation leads to injection. This vulnerability is referenced as CVE-2026-20283. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Cisco Identity Services Engine 3.3.0/3.4.0/3.5.0. Affected by this issue is an unknown functionality of the component IPsec Open API. The manipulation with an unknown input leads to a injection vulnerability. Using CWE to declare the problem leads to CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A vulnerability in the IPsec Open API endpoint of Cisco ISE could allow an authenticated, remote attacker to inject arbitrary commands on the underlying operating system.  This vulnerability is due to insufficient validation of user-supplied input in IPsec Open API calls. An attacker could exploit this vulnerability by sending crafted input to the IPsec Open API endpoint on an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system.  To exploit this vulnerability, the attacker must have valid administrative credentials and the node must have more than one network interface, one of which must be configured as an active IPsec tunnel. Note: For CVE-2026-20283, Cisco has assigned a Security Impact Rating (SIR) of High rather than Medium as the score indicates. The reason is that it is easy to get to root from the achieved privilege level.

The advisory is available at sec.cloudapps.cisco.com. This vulnerability is handled as CVE-2026-20283 since 10/08/2025. The exploitation is known to be easy. The attack may be launched remotely. The exploitation requires an enhanced level of successful authentication. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 09/16/2026). This vulnerability is assigned to T1055 by the MITRE ATT&CK project.

Upgrading eliminates this vulnerability.

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Productinfo

Type

• Policy Management Software

Vendor

• Cisco

Name

• Identity Services Engine

Version

• 3.3.0
• 3.4.0
• 3.5.0

License

• commercial

Website

• Vendor: https://www.cisco.com/

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