CVE-2025-20343 (GCVE-0-2025-20343)

Vulnerability from cvelistv5 – Published: 2025-11-05 16:31 – Updated: 2025-11-05 20:07
VLAI
Title
Cisco Identity Services Engine Radius Suppression Denial of Service Vulnerability
Summary
A vulnerability in the RADIUS setting Reject RADIUS requests from clients with repeated failures on Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to cause Cisco ISE to restart unexpectedly. This vulnerability is due to a logic error when processing a RADIUS access request for a MAC address that is already a rejected endpoint. An attacker could exploit this vulnerability by sending a specific sequence of multiple crafted RADIUS access request messages to Cisco ISE. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when Cisco ISE restarts.
Severity
8.6 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-11-05 20:06 UTC
CWE
Assigner
cisco CNA under the mitre root
CNA scorecard C 66/100 over 431 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Cisco Cisco Identity Services Engine Software Affected: 3.4.0
Affected: 3.4 Patch 1
Affected: 3.4 Patch 2
Affected: 3.4 Patch 3
guessed Create a notification for this product.
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