A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, remote attacker to execute arbitrary code on an affected device.
This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker with valid VPN user credentials could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as root, possibly resulting in the complete compromise of the affected device.
Is CVE-2025-20333 exploited?
Listed in the CISA KEV catalog on 2025-09-25.
Federal remediation due 2025-09-26.
Past that date by 323 days.
EPSS puts exploitation in the next 30 days at 40%.
Public exploit code: none found in monitored sources.