CVE-2025-20285

Q: What is the severity of CVE-2025-20285?

CVE-2025-20285 has a CVSS score of 4.1 (MEDIUM). This vulnerability allows authenticated remote attackers with administrative credentials to bypass IP access restrictions on Cisco ISE and ISE-PIC devices, enabling login from unauthorized IP addresses. It affects systems using the IP Access Restriction feature for access control. The risk is limited to attackers who already possess valid admin credentials.

4.1 MEDIUM

Authentication Bypass

📋 TL;DR

This vulnerability allows authenticated remote attackers with administrative credentials to bypass IP access restrictions on Cisco ISE and ISE-PIC devices, enabling login from unauthorized IP addresses. It affects systems using the IP Access Restriction feature for access control. The risk is limited to attackers who already possess valid admin credentials.

💻 Affected Systems

Products:

Cisco Identity Services Engine (ISE)
Cisco ISE-PIC

Versions: Specific versions are detailed in the Cisco advisory; check the vendor link for exact ranges.

Operating Systems: Cisco-specific OS for ISE devices

Default Config Vulnerable: ✅ No

Notes: Only affects systems with the IP Access Restriction feature configured; default configurations may not be vulnerable.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

An attacker with stolen admin credentials could gain unauthorized access from any IP address, potentially leading to full device compromise, data theft, or further network infiltration.

🟠

Likely Case

An insider or attacker with leaked credentials could bypass IP restrictions to access the device from an unexpected location, violating security policies but requiring prior credential compromise.

🟢

If Mitigated

With strong credential management and network segmentation, impact is minimal as attackers still need valid admin credentials to exploit.

🌐 Internet-Facing: MEDIUM, as internet-facing devices are exposed to credential attacks, but exploitation requires admin credentials, reducing likelihood.

🏢 Internal Only: MEDIUM, as internal attackers with credentials could bypass restrictions, but risk is lower if network controls are in place.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: LOW, as it involves simple API login attempts with valid credentials from unauthorized IPs.

Exploitation requires administrative credentials, making it dependent on credential compromise or insider threats.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Refer to Cisco advisory for patched versions; typically requires upgrading to a fixed release.

Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-multi-3VpsXOxO

Restart Required: Yes

Instructions:

1. Review the Cisco advisory for affected versions. 2. Download and apply the recommended patch from Cisco. 3. Restart the ISE device to apply changes. 4. Verify the fix by testing IP access restrictions.

🔧 Temporary Workarounds

Disable IP Access Restriction Feature

all

Temporarily disable the IP Access Restriction feature to prevent bypass, but this reduces access control.

Access ISE CLI or GUI, navigate to Admin Access > IP Access Restrictions, and disable the feature.

Enforce Strong Credential Policies

all

Implement multi-factor authentication and regular credential rotation to reduce risk of credential compromise.

Configure MFA in ISE settings and set up credential management policies.

🧯 If You Can't Patch

Restrict network access to ISE devices using firewall rules to only allow trusted IPs, compensating for the vulnerability.
Monitor logs for unauthorized login attempts from unexpected IPs and review admin credential usage regularly.

🔍 How to Verify

Check if Vulnerable:

Check if IP Access Restriction is enabled in ISE and test login from a disallowed IP with admin credentials; if successful, device is vulnerable.

Check Version:

Log into ISE CLI and run 'show version' to check the current software version.

Verify Fix Applied:

After patching, attempt login from a disallowed IP with admin credentials; access should be denied.

📡 Detection & Monitoring

Log Indicators:

Failed or successful login attempts from IPs not in the allowed list in ISE authentication logs.

Network Indicators:

Unusual API traffic to ISE from unauthorized source IPs.

SIEM Query:

Example: 'source="ISE" event_type="authentication" src_ip NOT IN allowed_ips'

📊 Metadata

CVE ID: CVE-2025-20285

CVSS v3 Score: 4.1 (MEDIUM)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:N

CWE: CWE-302

EPSS Score: 0.04% exploit probability (11.1th percentile)

Published: July 16, 2025

Last Updated: July 22, 2025

🔗 References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-multi-3VpsXOxO Vendor Advisory

📋 TL;DR

💻 Affected Systems

📦 What is this software?

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

Identity Services Engine Passive Identity Connector by Cisco

⚠️ Risk & Real-World Impact

Worst Case

Likely Case

If Mitigated

🎯 Exploit Status

🛠️ Fix & Mitigation

✅ Official Fix

Instructions:

🔧 Temporary Workarounds

Disable IP Access Restriction Feature

Enforce Strong Credential Policies

🧯 If You Can't Patch

🔍 How to Verify

Check if Vulnerable:

Check Version:

Verify Fix Applied:

📡 Detection & Monitoring

Log Indicators:

Network Indicators:

SIEM Query:

📊 Metadata

🔗 References

📤 Share & Export

🔗 Related Vulnerabilities