Cisco ISE and ISE-PIC Unauthenticated Remote Code Execution Vulnerability Advisory (CVE-2025-20281)
Executive & SecOps Summary
SECOPS ASSESSMENTSpecific API endpoints of Cisco Identity Services Engine (ISE) and Cisco ISE-PIC
An unauthenticated, remote attacker can execute arbitrary code with root privileges on the underlying operating system by sending a crafted API request
Immediately apply the official security patches provided by Cisco and restrict access to the management API ports
Affected Products & Version Scope
Remediation & Live Workaround Commands
PATCH & WORKAROUND1. Official Patch & Version Upgrade Commands
Apply the official hotfixes or patch bundles via the Cisco ISE CLI or Admin portal. To install the patch via CLI, use the following command:
# Access the Cisco ISE CLI and install the downloaded patch bundle
# Note: This process may restart services; schedule during a maintenance window.
ise/admin# patch install ise-patch-bundle.tar.gz repository remote_repo_name2. Temporary Workaround & Hardening Configuration
If patching cannot be applied immediately, restrict access to the ISE management and API ports (e.g., TCP 443, 8443) using network firewalls or Access Control Lists (ACLs):
# Example Cisco ASA/FTD ACL to restrict API access to trusted administrator subnets only
access-list ACL_ISE_HARDENING extended permit tcp 10.10.10.0 255.255.255.0 host 192.168.1.10 eq 443
access-list ACL_ISE_HARDENING extended permit tcp 10.10.10.0 255.255.255.0 host 192.168.1.10 eq 8443
access-list ACL_ISE_HARDENING extended deny tcp any host 192.168.1.10 eq 443
access-list ACL_ISE_HARDENING extended deny tcp any host 192.168.1.10 eq 84433. Log Audit & IoC Verification Commands
Inspect the application and system logs on the Cisco ISE appliance to identify potential exploitation attempts or unauthorized root access:
# Query application and system logs for suspicious API activity or root execution
ise/admin# show logging application ade.log | include 'api'
ise/admin# show logging application local-syslog | include 'root'Stop Exposing VPN Ports to the Internet — Switch to Zero-Trust Access
Eliminate public-facing VPN concentrators and firewall management ports with identity-first Zero-Trust Network Access.
Technical Root Cause & Exploitation Mechanics
1. Vulnerability Overview & Root Cause
This vulnerability (CVE-2025-20281) exists in a specific API of Cisco Identity Services Engine (ISE) and Cisco ISE-PIC due to insufficient validation of user-supplied input. An unauthenticated, remote attacker can exploit this flaw by submitting a specially crafted API request to the vulnerable endpoint, leading to command injection on the underlying operating system.
2. Exploitation Mechanics & Attack Scenario
The attack vector is network-based and requires no privileges or user interaction (AV:N/AC:L/PR:N/UI:N). An attacker sends a malicious HTTP request containing payload sequences designed to bypass input sanitization filters. Because the API processes this input without proper escaping, the payload is executed directly by the system shell, granting the attacker full root-level access to the appliance.
3. Infrastructure & Business Impact
Cisco ISE is a critical infrastructure component responsible for Network Access Control (NAC) and AAA services. With a CVSS score of 10.0 and its inclusion in the CISA KEV catalog, this vulnerability poses an extreme risk. Successful exploitation allows complete compromise of the ISE node, enabling attackers to manipulate network access policies, compromise active directory integrations, and pivot laterally across the enterprise network.
Official Vendor Advisories & References
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 attacker does not require any valid credentials to exploit this vulnerability. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by submitting a crafted API request. A successful exploit could allow the attacker to obtain root privileges on an affected device.
Frequently Asked SecOps Questions (CVE-2025-20281)
FAQQ1. How critical is CVE-2025-20281 and is it actively exploited in the wild?
CVE-2025-20281 is rated CVSS 10.0 (CRITICAL) with a 30-day EPSS exploitation probability of 97.6%. It is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, requiring immediate emergency remediation.
Q2. Which vendors and products are affected by CVE-2025-20281?
Primary impacted vendors include cisco across identity services engine, ise-pic. Scope summary: All deployments of Cisco Identity Services Engine (ISE) and Cisco ISE-PIC where the vulnerable API is accessible (refer to Cisco's official advisory for specific version details)
Q3. What temporary mitigations or workarounds exist for CVE-2025-20281 before patching?
[Mitigation] Immediately apply the official security patches provided by Cisco and restrict access to the management API ports Follow the CLI remediation commands and interactive SecOps checklist on this page to restrict exposure prior to your maintenance window.
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