Assessment
Why it matters
CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 85.6%; technical severity is CVSS 6.1.
Multiple vulnerabilities in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct cross-site scripting (XSS) attacks against a user of the web services interface of an affected device. The vulnerabilities are due to insufficient validation of user-supplied input by the web services interface of an affected device. An attacker could exploit these vulnerabilities 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. Note: These vulnerabilities affect only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.
Who should care
- Teams operating Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD), Adaptive Security Appliance Software, Secure Firewall Threat Defense
- Vulnerability and exposure management teams
- Security operations teams monitoring exploitation activity
Response plan
What I would do
- Confirm whether Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD), Adaptive Security Appliance Software, Secure Firewall Threat Defense is present in the environment.
- Identify affected versions and establish whether vulnerable services are exposed or reachable.
- Apply updates per vendor instructions.
- Review relevant security telemetry for evidence of attempted or successful exploitation.
- Document the remediation decision and track it to verified completion.
Vendor remediation
Patch and remediation links
Use the vendor source below to confirm the correct fixed version, package or mitigation for your affected product.
Technical details
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- CWE
- CWE-79
- Affected versions
- Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD); Cisco Adaptive Security Appliance Software (Start Including: 9.15, End Excluding: 9.15.1.15); Cisco Secure Firewall Threat Defense (Start Including: 6.7.0, End Excluding: 6.7.0.2)
- Published
- 21 October 2020
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
Signal timeline
- CVE published
- Added to CISA KEV
- Latest EPSS score: 85.6%
- Signal calculated at 83