CVE-2025-20281: 
Cisco ISE vulnerability analysis and mitigation

A vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC could allow an unauthenticated, remote attacker to execute arbitrary code on the underlying operating system as root. The vulnerability (CVE-2025-20281) was discovered and disclosed on June 25, 2025, affecting Cisco ISE and ISE-PIC releases 3.3 and later. This critical security flaw does not require any valid credentials to exploit (Cisco Advisory).

The vulnerability stems from insufficient validation of user-supplied input in a specific API. The flaw has been assigned a CVSS v3.1 base score of 9.8 CRITICAL (Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) and is classified under CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component). The vulnerability can be exploited by submitting a crafted API request to the affected system (NVD, Cisco Advisory).

A successful exploitation of this vulnerability allows an attacker to execute arbitrary code on the underlying operating system with root privileges. This level of access provides complete control over the affected device, potentially compromising the entire system's security (Cisco Advisory).

Cisco has released software updates to address this vulnerability. For ISE 3.3, users should upgrade to 3.3 Patch 6 (ise-apply-CSCwo994493.3.0.430patch4-SPA.tar.gz), and for ISE 3.4, upgrade to 3.4 Patch 2 (ise-apply-CSCwo994493.4.0.608patch1-SPA.tar.gz). There are no workarounds available for this vulnerability (Cisco Advisory).