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Vulnerability record · CVE-2026-20070 · published 4 March 2026

CVE-2026-20070: Cisco adaptive security appliance software vulnerability

Cisco · Adaptive Security Appliance Software

A vulnerability in the VPN web services component of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall 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 in HTTP requests. An attacker could exploit this vulnerability by persuading a user to follow a link to a malicious website that is 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 VPN web server.

6.1 CVSS 3.1 Medium EPSS 0.26% · top 83.6% CWE-80 · CWE-80
6.1CVSS 3.1 base score
0.26%EPSS exploitation probability, 30 days
NoNot in CISA KEV
2Affected product versions listed by NVD
1References
11 Aug 2026Last modified by NVD

Description

A vulnerability in the VPN web services component of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall 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 in HTTP requests. An attacker could exploit this vulnerability by persuading a user to follow a link to a malicious website that is 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 VPN web server.

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-webvpn-xss-uwjc4HR Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-20070), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.