CVE-2024-20256

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 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.

Published: 2024-05-15 Last update: 2025-08-07 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-20256 is rated Low Risk (26.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.29%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-20256

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.12% 0.29% +0.17%
2 2025-11-21 0.18% 0.12% -0.05%
3 2025-11-18 — 0.18% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-20256

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 1.7 2.7 [email protected]

Weakness enumeration for CVE-2024-20256

Affected software / configurations for CVE-2024-20256

Vendor Product Version Raw CPE
cisco asyncos 11.7.0-406 cpe:2.3:o:cisco:asyncos:11.7.0-406:*:*:*:*:*:*:*
cisco asyncos 11.7.0-418 cpe:2.3:o:cisco:asyncos:11.7.0-418:*:*:*:*:*:*:*
cisco asyncos 11.7.1-006 cpe:2.3:o:cisco:asyncos:11.7.1-006:*:*:*:*:*:*:*
cisco asyncos 11.7.1-020 cpe:2.3:o:cisco:asyncos:11.7.1-020:*:*:*:*:*:*:*
cisco asyncos 11.7.1-049 cpe:2.3:o:cisco:asyncos:11.7.1-049:*:*:*:*:*:*:*
cisco asyncos 11.7.2-011 cpe:2.3:o:cisco:asyncos:11.7.2-011:*:*:*:*:*:*:*
cisco asyncos 11.8.0-414 cpe:2.3:o:cisco:asyncos:11.8.0-414:*:*:*:*:*:*:*
cisco asyncos 11.8.1-023 cpe:2.3:o:cisco:asyncos:11.8.1-023:*:*:*:*:*:*:*
cisco asyncos 11.8.3-018 cpe:2.3:o:cisco:asyncos:11.8.3-018:*:*:*:*:*:*:*
cisco asyncos 11.8.3-021 cpe:2.3:o:cisco:asyncos:11.8.3-021:*:*:*:*:*:*:*
cisco asyncos 12.0.1-268 cpe:2.3:o:cisco:asyncos:12.0.1-268:*:*:*:*:*:*:*
cisco asyncos 12.0.3-007 cpe:2.3:o:cisco:asyncos:12.0.3-007:*:*:*:*:*:*:*
cisco asyncos 12.5.1-011 cpe:2.3:o:cisco:asyncos:12.5.1-011:*:*:*:*:*:*:*
cisco asyncos 12.5.2-007 cpe:2.3:o:cisco:asyncos:12.5.2-007:*:*:*:*:*:*:*
cisco asyncos 12.5.4-005 cpe:2.3:o:cisco:asyncos:12.5.4-005:*:*:*:*:*:*:*
cisco asyncos 12.5.5-004 cpe:2.3:o:cisco:asyncos:12.5.5-004:*:*:*:*:*:*:*
cisco asyncos 12.5.6-008 cpe:2.3:o:cisco:asyncos:12.5.6-008:*:*:*:*:*:*:*
cisco asyncos 14.0.2-012 cpe:2.3:o:cisco:asyncos:14.0.2-012:*:*:*:*:*:*:*
cisco asyncos 14.0.3-014 cpe:2.3:o:cisco:asyncos:14.0.3-014:*:*:*:*:*:*:*
cisco asyncos 14.0.4-005 cpe:2.3:o:cisco:asyncos:14.0.4-005:*:*:*:*:*:*:*
cisco asyncos 14.5.0-498 cpe:2.3:o:cisco:asyncos:14.5.0-498:*:*:*:*:*:*:*
cisco asyncos 14.5.1-016 cpe:2.3:o:cisco:asyncos:14.5.1-016:*:*:*:*:*:*:*
cisco asyncos 15.0.0-322 cpe:2.3:o:cisco:asyncos:15.0.0-322:*:*:*:*:*:*:*
cisco secure_email_and_web_manager_virtual_appliance_m100v — cpe:2.3:a:cisco:secure_email_and_web_manager_virtual_appliance_m100v:-:*:*:*:*:*:*:*
cisco secure_email_and_web_manager_virtual_appliance_m300v — cpe:2.3:a:cisco:secure_email_and_web_manager_virtual_appliance_m300v:-:*:*:*:*:*:*:*
cisco secure_email_and_web_manager_virtual_appliance_m600v — cpe:2.3:a:cisco:secure_email_and_web_manager_virtual_appliance_m600v:-:*:*:*:*:*:*:*
cisco asyncos 9.0.0-087 cpe:2.3:o:cisco:asyncos:9.0.0-087:*:*:*:*:*:*:*
cisco asyncos 11.0.0-115 cpe:2.3:o:cisco:asyncos:11.0.0-115:*:*:*:*:*:*:*
cisco asyncos 11.0.1-161 cpe:2.3:o:cisco:asyncos:11.0.1-161:*:*:*:*:*:*:*
cisco asyncos 11.5.1-105 cpe:2.3:o:cisco:asyncos:11.5.1-105:*:*:*:*:*:*:*
cisco asyncos 12.0.0-452 cpe:2.3:o:cisco:asyncos:12.0.0-452:*:*:*:*:*:*:*
cisco asyncos 12.0.1-011 cpe:2.3:o:cisco:asyncos:12.0.1-011:*:*:*:*:*:*:*
cisco asyncos 12.5.0-636 cpe:2.3:o:cisco:asyncos:12.5.0-636:*:*:*:*:*:*:*
cisco asyncos 12.5.0-658 cpe:2.3:o:cisco:asyncos:12.5.0-658:*:*:*:*:*:*:*
cisco asyncos 12.5.0-670 cpe:2.3:o:cisco:asyncos:12.5.0-670:*:*:*:*:*:*:*
cisco asyncos 12.5.0-678 cpe:2.3:o:cisco:asyncos:12.5.0-678:*:*:*:*:*:*:*
cisco asyncos 12.8.1-002 cpe:2.3:o:cisco:asyncos:12.8.1-002:*:*:*:*:*:*:*
cisco asyncos 12.8.1-021 cpe:2.3:o:cisco:asyncos:12.8.1-021:*:*:*:*:*:*:*
cisco asyncos 13.0.0-277 cpe:2.3:o:cisco:asyncos:13.0.0-277:*:*:*:*:*:*:*
cisco asyncos 13.6.2-078 cpe:2.3:o:cisco:asyncos:13.6.2-078:*:*:*:*:*:*:*
cisco asyncos 13.8.1-068 cpe:2.3:o:cisco:asyncos:13.8.1-068:*:*:*:*:*:*:*
cisco asyncos 13.8.1-074 cpe:2.3:o:cisco:asyncos:13.8.1-074:*:*:*:*:*:*:*
cisco asyncos 13.8.1-108 cpe:2.3:o:cisco:asyncos:13.8.1-108:*:*:*:*:*:*:*
cisco asyncos 14.0.0-404 cpe:2.3:o:cisco:asyncos:14.0.0-404:*:*:*:*:*:*:*
cisco asyncos 14.1.0-223 cpe:2.3:o:cisco:asyncos:14.1.0-223:*:*:*:*:*:*:*
cisco asyncos 14.1.0-227 cpe:2.3:o:cisco:asyncos:14.1.0-227:*:*:*:*:*:*:*
cisco asyncos 14.2.0-212 cpe:2.3:o:cisco:asyncos:14.2.0-212:*:*:*:*:*:*:*
cisco asyncos 14.2.0-224 cpe:2.3:o:cisco:asyncos:14.2.0-224:*:*:*:*:*:*:*
cisco asyncos 14.2.1-020 cpe:2.3:o:cisco:asyncos:14.2.1-020:*:*:*:*:*:*:*
cisco asyncos 14.3.0-120 cpe:2.3:o:cisco:asyncos:14.3.0-120:*:*:*:*:*:*:*
cisco asyncos 15.0.0-334 cpe:2.3:o:cisco:asyncos:15.0.0-334:*:*:*:*:*:*:*

References for CVE-2024-20256

cvelogic Threat Intelligence