{"id":64278,"date":"2025-08-24T03:12:12","date_gmt":"2025-08-24T03:12:12","guid":{"rendered":""},"modified":"2025-10-02T23:37:09","modified_gmt":"2025-10-03T05:37:09","slug":"cve-2025-20263-critical-buffer-overflow-vulnerability-in-cisco-secure-firewall","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-20263-critical-buffer-overflow-vulnerability-in-cisco-secure-firewall\/","title":{"rendered":"CVE-2025-20263: Critical Buffer Overflow Vulnerability in Cisco Secure Firewall<\/strong>"},"content":{"rendered":"

Overview<\/strong><\/p>\n

The cybersecurity community has recently identified a critical vulnerability, CVE-2025-20263, that affects Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software. This vulnerability has the potential to compromise the stability and security of systems running these applications, making it a significant threat to organizations that rely on Cisco’s secure firewall services. Its severity is underscored by its high CVSS score and the potential for system compromise<\/a> or data leakage.<\/p>\n

Vulnerability Summary<\/strong><\/p>\n

CVE ID: CVE-2025-20263
\nSeverity: Critical (8.6 CVSS Score)
\nAttack Vector: Network
\nPrivileges Required: None
\nUser Interaction: None
\nImpact: A successful exploit could cause a buffer overflow<\/a> condition that leads to a system reload, resulting in a denial of service (DoS) condition. This could potentially lead<\/a> to system compromise or data leakage.<\/p>\n

Affected Products<\/strong><\/p>\n

Product | Affected Versions<\/p>\n

Cisco Secure Firewall ASA Software<\/a> | All current versions until patched
\nCisco Secure Firewall FTD Software<\/a> | All current versions until patched<\/p>\n

How the Exploit Works<\/strong><\/p>\n

The vulnerability is due to insufficient boundary checks for specific data<\/a> provided to the web services interface of an affected system. An attacker could exploit this vulnerability<\/a> by sending a maliciously crafted HTTP request to the affected system. The improper boundary checks facilitate a buffer overflow<\/a> condition, causing the system to reload and leading to a DoS condition.<\/p>\n

Conceptual Example Code<\/strong><\/p>\n

Below is a conceptual example of how an attacker might exploit this vulnerability using a malicious HTTP request:<\/a><\/p>\n

POST \/asa_endpoint HTTP\/1.1\nHost: target.example.com\nContent-Type: application\/xml\n{ \"payload\": \"\" }<\/code><\/pre>\n
In this example, the attacker sends a POST request with a payload containing XML data that exceeds the buffer capacity of the system’s<\/a> web services interface. This triggers a buffer overflow<\/a> condition, which in turn causes the system to reload and results in a denial of service.<\/p>\n
Mitigation Guidance<\/strong><\/p>\n
Users are advised to apply vendor patches as soon as they become available to remediate this vulnerability<\/a>. In the absence of a patch, users can utilize Web Application Firewall (WAF) or Intrusion Detection Systems (IDS) as temporary mitigation measures. These tools can help to monitor network traffic for malicious activity and prevent any potential exploitation of this vulnerability<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"
Overview The cybersecurity community has recently identified a critical vulnerability, CVE-2025-20263, that affects Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software. This vulnerability has the potential to compromise the stability and security of systems running these applications, making it a significant threat to organizations that rely on […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"footnotes":""},"categories":[1],"tags":[],"vendor":[96],"product":[],"attack_vector":[86,87],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-64278","post","type-post","status-publish","format-standard","hentry","category-uncategorized","vendor-cisco","attack_vector-buffer-overflow","attack_vector-dos"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t