Cisco Security Advisoriescisco-sa-ise-xss-Uz9VWRQ

Cisco Identity Services Engine Cross-Site Scripting Vulnerability

A vulnerability in the web-based management interface of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to conduct a reflected cross-site scripting (XSS) attack against a user of the interface. This vulnerability exists because the web-based management interface does not properly validate user-supplied input. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-xss-Uz9VWRQ This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories. In addition, for further documentation of improvements and fixes in Cisco Identity Services Engine, see Cisco Identity Services Engine Security Hardening Release: September 2026. Security Impact Rating: Medium CVE: CVE-2026-20309

Read the vendor bulletin

MediumCVSS not listedMedium severity

Scope

What the vendor says is affected

The collected bulletin did not provide a separate affected-products list. Check the original bulletin before making an exposure decision.

Next step

What the vendor recommends

Cisco has released software updates that address this vulnerability.

Review the complete instructions on the vendor's site

Timeline

When this advisory changed

Sep 16, 2026 at 4:00 PM UTC
Published by Cisco
The publication date reported by the vendor.
Sep 16, 2026 at 4:10 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 26, 2026 at 6:40 PM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory

CVE-2026-20309View CVSS, KEV, EPSS, and threat context

Source

Start with the vendor's bulletin

SecurityAlert organizes the fields the vendor published. The original bulletin remains the source of record for affected versions, fixes, and later changes.

Vendor: Cisco
Advisory ID: cisco-sa-ise-xss-Uz9VWRQ
Last source check: Sep 26, 2026 at 6:40 PM UTC

Open the official bulletin How SecurityAlert builds this record

Your environment

Check the systems you actually run

A vendor advisory can tell you what may be affected. It cannot tell you whether that product and version are installed in your environment.

Confirm the product and installed version.
Read the vendor's prerequisites and exceptions.
Test the update or mitigation through your normal change process.

Keep following

Get new Cisco advisories

Use the vendor-specific RSS feed or set up alerts for a product your team relies on.

Follow this vendor's RSS feed

What the vendor says is affected

What the vendor recommends

When this advisory changed

CVEs named in this advisory

Related advisories from Cisco

Cisco Identity Services Engine Authentication Bypass Vulnerabilities

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software SSL VPN Denial of Service Vulnerability

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Logging Denial of Service Vulnerability

Cisco Secure Firewall Adaptive Security Appliance, Secure Firewall Threat Defense, and Secure Firewall Management Center Software Hardening Release: September 2026

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software for Secure Firewall 3100 and 4200 Series DTLS Denial of Service Vulnerability

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software IKEv2 Certificate Authentication Denial of Service Vulnerability