CVE-2025-20337: 
Cisco ISE vulnerability analysis and mitigation

A critical vulnerability (CVE-2025-20337) was discovered in Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC). The vulnerability allows an unauthenticated, remote attacker to execute arbitrary code on the underlying operating system with root privileges. The flaw was discovered in July 2025 and affects ISE and ISE-PIC releases 3.3 and 3.4, while versions 3.2 and earlier are not vulnerable (Cisco Advisory, Bleeping Computer).

CVE-2025-20337 received a maximum CVSS score of 10.0 with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H. The vulnerability is caused by insufficient validation of user-supplied input in a specific API. An attacker could exploit this vulnerability by submitting a crafted API request without requiring any valid credentials (Cisco Advisory).

A successful exploitation of CVE-2025-20337 could allow an attacker to obtain root privileges on an affected device, execute arbitrary code on the underlying operating system, and gain complete control over the vulnerable system (Security Affairs, Cisco Advisory).

Cisco has released patches to address CVE-2025-20337. For Cisco ISE Release 3.3, users should upgrade to version 3.3 Patch 7, and for Release 3.4, users should upgrade to version 3.4 Patch 2. There are no workarounds available for this vulnerability. Systems with hot patches ise-apply-CSCwo994493.3.0.430patch4-SPA.tar.gz or ise-apply-CSCwo994493.4.0.608patch1-SPA.tar.gz should be updated as these patches do not address CVE-2025-20337 (Cisco Advisory).

The vulnerability was discovered and reported by Kentaro Kawane of GMO Cybersecurity through the Trend Micro Zero Day Initiative. The discovery has garnered significant attention in the cybersecurity community due to its critical severity rating and the potential for remote code execution (Hacker News, Security Affairs).