CVE-2020-3420

MEDIUM
Published Nov 18, 2024 Modified Aug 6, 2025 CWE-79

Description

A vulnerability in the web-based management interface of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an authenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the interface. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of the affected software. An attacker could exploit this vulnerability by inserting malicious data into a specific data field in 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.There are no workarounds that address this vulnerability.

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CVSS v3.1 Score

5.4
MEDIUM
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor Product
cisco unified_communications_manager

References

Frequently Asked Questions

What is CVE-2020-3420? +
A vulnerability in the web-based management interface of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an authenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the interface. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of the affected software. An attacker could exploit this vulnerability by inserting malicious data into a specific data field in 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.There are no workarounds that address this vulnerability. It has a CVSS v3.1 base score of 5.4 (MEDIUM).
How severe is CVE-2020-3420? +
CVE-2020-3420 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2020-3420? +
CVE-2020-3420 affects products from cisco, specifically: unified_communications_manager. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2020-3420? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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