Description
A vulnerability in the Clientless SSL VPN (WebVPN) portal of Cisco Adaptive Security Appliance (ASA) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the web-based management interface of an affected device. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or allow the attacker to access sensitive browser-based information.
Affected products
cisco: adaptive security appliance; cisco: adaptive security appliance software; cisco: asa 5505; cisco: asa 5510; cisco: asa 5512-x; cisco: asa 5515-x; cisco: asa 5520; cisco: asa 5525-x; cisco: asa 5550; cisco: asa 5555-x; cisco: asa 5580; cisco: asa 5585-x; cisco: secure firewall threat defense
References2
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/c… Vendor Advisory
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/c… Vendor Advisory
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
- 1% percentile: 65 · as of 10 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
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