CVE-2026-20309

MEDIUM

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) attac...

Affects 0 products across 1 vendor.

CVSS 3.16.1
EPSS0.2%
Percentile8th
PatchUnknown
CVSS Vector — Plain English Remotely exploitable over the network, low complexity, no authentication required, requires user interaction, can impact systems beyond the vulnerable component, no availability impact.
CWE Weakness Definitions
CWE-79: Cross-Site Scripting (XSS)

Attacker injects malicious scripts into web pages viewed by other users, executing in the victim's browser context.

Related Attack Patterns (CAPEC)
CAPEC-85 AJAX Footprinting
via CWE-79
CAPEC-209 XSS Using MIME Type Mismatch
via CWE-79
CAPEC-588 DOM-Based XSS
via CWE-79
CAPEC-591 Reflected XSS
via CWE-79
CAPEC-592 Stored XSS
via CWE-79
Show all 6
via CWE-79

Mapping is CWE-to-CAPEC per MITRE CAPEC 3.9.

◆ AI Analysis — automated analysis, not human-reviewed

A medium severity vulnerability (CVE-2026-20309) affects the target system. 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 vulnerabil...

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Frequently Asked Questions
What is CVE-2026-20309?
A medium severity vulnerability (CVE-2026-20309) affects the target system. 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 vulnerabil...
What is the CVSS score for CVE-2026-20309?
CVE-2026-20309 has CVSS 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N. EPSS: 0.2%.
Is CVE-2026-20309 actively exploited?
No confirmed active exploitation of CVE-2026-20309 as of 2026-09-25.
How do I remediate CVE-2026-20309?
Apply vendor patches for CVE-2026-20309. Monitor Cisco advisories.
What systems are affected by CVE-2026-20309?
CVE-2026-20309 affects: Cisco.
Vulnerability Details
CVE IDCVE-2026-20309
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Published2026-09-16
Last Modified2026-09-18
ICS Relevance55%
Weakness (CWE)
Cross-Site Scripting (XSS)
SourceNVD
Official Description

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.

Source: NIST NVD / MITRE CVE Database

Affected Products
VendorProductFixed Version
Cisco — —
Remediation

No patch URL on record. Monitor vendor security advisories directly.

Threat Intelligence
● Threat Intelligence Validated: September 2026 | Threat Age: 11 Days
CISA KEVNot in KEV catalog
Public ExploitNot confirmed
PoC CodeNot confirmed
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