CVE-2025-20263: Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Buffer Overflow Denial of Service Vulnerability

DescriptionCVE.org

A vulnerability in the web services interface of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected system. This vulnerability is due to insufficient boundary checks for specific data that is provided to the web services interface of an affected system. An attacker could exploit this vulnerability by sending a crafted HTTP request to the affected system. A successful exploit could allow the attacker to cause a buffer overflow condition on the affected system, which could cause the system to reload, resulting in a denial of service (DoS) condition.

• Cisco · Cisco Adaptive Security Appliance (ASA) Software9.12.3; 9.8.3; 9.12.1; 9.8.1; 9.12.2; 9.8.2.45 and 208 more
• Cisco · Cisco Firepower Threat Defense Software6.2.3.14; 6.4.0.1; 6.2.3.7; 6.2.3; 6.4.0.2; 6.2.3.9 and 86 more

Exploitation

Unlikely (under 1%). EPSS under 1%, or no score yet.

CISA KEV

Not listed

Public check

No public nuclei template

Weakness

Integer Overflow to Buffer Overflow · Memory Corruption

Vendor

Cisco

Published

August 2025

Band

Unlikely (under 1%), August 2025

• NVD entrynvd.nist.gov
• CVE recordcve.org
• Weakness CWE-680cwe.mitre.org
• sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvsec.cloudapps.cisco.com