Description
A vulnerability in the VPN web client services feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a browser that is accessing an affected device. This vulnerability is due to improper validation of user-supplied input to application endpoints. An attacker could exploit this vulnerability by persuading a user to follow a link designed to submit malicious input to the affected application. A successful exploit could allow the attacker to execute arbitrary HTML or script code in the browser in the context of the web services page.
Affected products
cisco: adaptive security appliance software; cisco: secure firewall threat defense
References4
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Vendor Advisory
- sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-7… Vendor Advisory
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Broken Link
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Broken Link
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 6 November 2026
- CWE
- CWE-80CWE-79
Could this be exploited in your environment?
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