CVE-2026-20283

CVE CVE-2026-20283EUVD EUVD-2026-81137Published 2026-09-16T20:15:27.000ZLast changed 2026-09-17T11:39:22.000ZCVSS 6.5

What the advisory describes

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.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Cisco — Cisco Identity Services Engine Software 3.5 Patch 2; 3.4 Patch 1; 3.4 Patch 3; 3.4 Patch 6; 3.4 Patch 5; 3.3.0; 3.3 Patch 6; 3.3 Patch 1; 3.5 Patch 1; 3.5.0; 3.3 Patch 11; 3.4 Patch 4; 3.3 Patch 5; 3.3 Patch 2; 3.3 Patch 3; 3.4 Patch 2; 3.3 Patch 7; 3.4.0; 3.3 Patch 4; 3.5 Patch 3; 3.3 Patch 9; 3.3 Patch 8; 3.3 Patch 10

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

Cisco — Identity Services Engine Software

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