CVE-2020-3580
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.
Key facts
- CVSS score
- 6.1 (v3.1)
- Severity
- MEDIUM
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N- Weakness (CWE)
- CWE-79
- EPSS score
- 85.6% (100th percentile)
- In CISA KEV
- Yes, added November 3, 2021
- In EU EUVD
- Yes (EUVD-2020-24851)
- Published
- October 21, 2020
- NVD last modified
- August 11, 2026
- Status
- Analyzed
CISA Known Exploited Vulnerability
Cisco ASA and FTD Cross-Site Scripting (XSS) Vulnerability
Added to the KEV catalog on November 3, 2021; federal remediation due May 3, 2022. Known to be used in ransomware campaigns.
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2020-24851 in the EU Vulnerability Database. ENISA flags it as known exploited. Last updated in EUVD on October 21, 2025.
View on the EU Vulnerability DatabaseAffected products
- cisco / adaptive security appliance software
- cisco / secure firewall threat defense
Certified products that may be affected
1 FIPS 140 or Common Criteria certified product, from automated matching by sec-certs.org.
- Cisco Adaptive Security Appliances Version: ASA software version 9.1(2) Components: ASA 5500 (5505, 5510, 5520, 5540, 5550, 5580-20-40), ASA 5500-X Series (5512-X, 5515-X, 5525-X, 5545-X, 5555-X), ASA 5585-X (5585-10, 5585-20, 5585-40, 5585-60), ASA Services Module (ASA-SM) - Cisco Systems, Inc. - Common Criteria Certificate Number: 2013/86 - archived
References
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-xss-multiple-FCB3vPZe(Patch, Vendor Advisory)
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3580(US Government Resource)
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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