netVigilance Vulnerability intelligence since 2004
CVE-2025-20333 · netVigilance record NV25-0177

Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow

past due

What to do

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.

CISA deadline 2025-09-26 · passed 11 months ago · applies to US federal civilian agencies; used elsewhere as a reference SLA

What happened

Cisco Secure Firewall Adaptive Security (ASA) Appliance and Secure Firewall Threat Defense (FTD) Software VPN Web Server contain a buffer overflow vulnerability that allows for remote code execution. This vulnerability could be chained with CVE-2025-20362.

Who is affected

Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense. Affected version ranges are listed in the vendor advisory and the NVD entry linked under Sources.

Weakness class: CWE-120.

Timeline

  1. Added to CISA KEVExploitation in the wild confirmed by CISA
  2. CISA remediation deadlinepassed 11 months ago

Sources