Cyber Resilience

CVE-2020-3420

Medium

Published: 18 November 2024

Published
18 November 2024
Modified
06 August 2025
KEV Added
Patch
CVSS Score v3 5.4 CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0013 31.8th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-3420 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Cisco Unified Communications Manager. Its CVSS base score is 5.4 (Medium).

Operationally, ranked at the 31.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

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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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

cisco
unified communications manager
all versions

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References