Cyber Resilience

CVE-2024-20256

Medium

Published: 15 May 2024

Published
15 May 2024
Modified
07 August 2025
KEV Added
Patch
CVSS Score v3.1 4.8 CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0013 31.2th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2024-20256 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Cisco Asyncos. Its CVSS base score is 4.8 (Medium).

Operationally, ranked at the 31.2th 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 AsyncOS Software for Cisco Secure Email and Web Manager and Secure Web Appliance could allow an authenticated, remote attacker to conduct an XSS attack against a user of the interface. This…

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vulnerability is due to insufficient validation of user input. An attacker could exploit this vulnerability by persuading a user of an affected 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.

CWE(s)

Related Threats

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

Affected Assets

cisco
asyncos
11.0.0-115, 11.0.1-161, 11.5.1-105, 11.7.0-406, 11.7.0-418
cisco
secure email and web manager virtual appliance m100v
all versions
cisco
secure email and web manager virtual appliance m300v
all versions
cisco
secure email and web manager virtual appliance m600v
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