Actively exploited in the wild
Cisco Secure Firewall Adaptive Security (ASA) Appliance and Secure Firewall Threat Defense (FTD) Missing Authorization Vulnerability
Cisco - Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense · Listed in the CISA KEV since 2025-09-25. This indicates confirmed attacks in production environments.
Required action: The KEV due date refers to the deadline by which FCEB agencies are expected to review and begin implementing the guidance outlined in Emergency Directive (ED) 25-03 (URL listed below in Notes). Agencies must follow the mitigation steps provided by CISA (URL listed below in Notes) and vendor’s instructions (URL listed below in Notes). Adhere to the applicable BOD 22-01 guidance for cloud services or discontinue use of the product if mitigations are not available.
CVE-2025-20362
MediumCVSS 6.5KEVExploitation Probability (EPSS)
Very high risk100th percentile - higher than 100% of all known CVEs
Summary
A vulnerability in the VPN web server of Cisco Secure Firewall ASA and FTD Software allows an unauthenticated, remote attacker to access restricted URL endpoints related to remote access VPN that should be inaccessible without authentication. The issue is due to improper validation of user-supplied input in HTTP(S) requests. A successful exploit could allow access to a restricted URL without authentication.
Risk Assessment
Risk of unauthorized access to VPN functionality, potentially leading to network security breaches and further attacks.
Recommendation
Apply Cisco patches and monitor HTTP traffic for unusual requests to the VPN server.
Original NVD description (English source)
Update: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Software or Cisco Secure FTD Software releases that are affected by CVE-2025-20333 and CVE-2025-20362. This attack can cause unpatched devices to unexpectedly reload, leading to denial of service (DoS) conditions. Cisco strongly recommends that all customers upgrade to the fixed software releases that are listed in the Fixed Software ["#fs"] section of this advisory. 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 unauthenticated, remote attacker to access restricted URL endpoints that are related to remote access VPN that should otherwise be inaccessible without authentication. This vulnerability is due to improper validation of user-supplied input in HTTP(S) requests. An attacker could exploit this vulnerability by sending crafted HTTP requests to a targeted web server on a device. A successful exploit could allow the attacker to access a restricted URL without authentication.