known ransomware use

Cisco Adaptive Security Appliance and Firepower Threat Defense Unauthorized Access Vulnerability

Added to KEV
2023-09-13
Federal due date
2023-10-04
Vendor
Cisco
Product
Adaptive Security Appliance and Firepower Threat Defense
EPSS
79.2th percentile (score 0.012, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2023-20269

CISA short description

Cisco Adaptive Security Appliance and Firepower Threat Defense contain an unauthorized access vulnerability that could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or establish a clientless SSL VPN session with an unauthorized user.

Required action

Apply mitigations per vendor instructions for group-lock and vpn-simultaneous-logins or discontinue use of the product for unsupported devices.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.