CVE-2021-1604

CVE-2021-1604 is a medium-severity vulnerability in Cisco Identity Services Engine with a CVSS 3.x base score of 4.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Description

Multiple vulnerabilities in the web-based management interface of Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to conduct a stored cross-site scripting (XSS) attack against a user. These vulnerabilities exist because the web-based management interface does not sufficiently validate user-supplied input. An attacker could exploit these vulnerabilities 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 affected interface or access sensitive, browser-based information. To exploit these vulnerabilities, the attacker would need valid administrative credentials.

Frequently asked questions

What is CVE-2021-1604?
Multiple vulnerabilities in the web-based management interface of Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to conduct a stored cross-site scripting (XSS) attack against a user. These vulnerabilities exist because the web-based management interface does not sufficiently validate user-supplied input. An attacker could exploit these vulnerabilities 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 affected interface or access sensitive, browser-based information. To exploit these vulnerabilities, the attacker would need valid administrative credentials.
How severe is CVE-2021-1604?
CVE-2021-1604 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-1604 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1604?
CVE-2021-1604 primarily affects Cisco Identity Services Engine. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1604?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1604 published?
CVE-2021-1604 was published on 2021-07-08 and last updated on 2026-06-17.

References

Affected products (17)

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