CVE-2020-3580Actively exploitedAdded to KEV 2021-11-03Known ransomware campaign use

Cisco ASA and FTD Cross-Site Scripting (XSS) Vulnerability

Cisco, Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD)

Description

Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an insufficient input validation vulnerability for user-supplied input by the web services interface. Successful exploitation could allow an attacker to perform cross-site scripting (XSS) in the context of the interface or access sensitive browser-based information.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

85.6%

estimated chance of real-world exploitation in the next 30 days, higher than 99.7% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2022-05-03

CWE-79

Talk to us about this

Penetration Testing

Confirm whether this vulnerability class is actually exploitable in your environment.

Security Engineering

Get help implementing the required action and closing the gap.

Our guide to vulnerability management and patch prioritization

View on CISA's KEV catalog View on NVD

Not sure if this affects you?

We help organizations confirm real exposure and prioritize what actually needs fixing first.

Request a Security Assessment Browse Services