CVE-2025-20263: cisco cisco adaptive security appliance (asa) software Integer Overflow to Buffer Overflow

Vulnerability summary

CVE-2025-20263 is a high (CVSS 8.6) Integer Overflow to Buffer Overflow vulnerability in cisco cisco adaptive security appliance (asa) software. EPSS estimates a 0.68% chance of exploitation in the next 30 days, higher than 51.3% of scored vulnerabilities.

Timeline

1. 14-08-2025
   PublishedVulnerability first disclosed.
2. 14-08-2025
   Last modifiedVulnerability information updated.

Description

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.

• CWE-680Integer Overflow to Buffer OverflowThe product performs a calculation to determine how much memory to allocate, but an integer overflow can occur that causes less memory to be allocated than expected, leading to a buffer overflow.