CVE-2021-34759: Cisco Identity Services Engine Cross-Site Scripting Vulnerability

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-02 · updated 2026-06-17
Weakness: CWE-79

Description

A vulnerability in the web-based management interface of Cisco Identity Services Engine (ISE) Software could allow an authenticated, remote attacker with administrative credentials to conduct a 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 injecting malicious code into specific pages of the interface. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or access sensitive, browser-based information. To exploit this vulnerability, an attacker would need valid administrative credentials.

Affected products

Cisco Identity Services Engine: before 2.2.0; 2.2.0, 2.2.0-patch1, 2.2.0-patch10, 2.2.0-patch12, 2.2.0-patch13, 2.2.0-patch14 (+50) — fixed in 2.2.0

How to fix

Upgrade to a fixed version: Cisco Identity Services Engine 2.2.0. Check the vendor advisory for mitigations.

References

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