CVE-2021-22992: 
F5 BIG-IP Advanced Firewall Manager vulnerability analysis and mitigation

CVE-2021-22992 is a critical buffer overflow vulnerability affecting F5's BIG-IP Advanced WAF/ASM systems. The vulnerability was discovered in March 2021 and affects BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, 12.1.x before 12.1.5.3, and 11.6.x before 11.6.5.3. This vulnerability received a CVSS score of 9.0, indicating high severity (NVD, Rapid7).

The vulnerability occurs when a malicious HTTP response is sent to an Advanced WAF/BIG-IP ASM virtual server that has a Login Page configured in its policy. This can trigger a buffer overflow condition in the system. The vulnerability specifically involves improper handling of HTTP response headers by the web application firewall. According to security researchers, the vulnerable condition is triggered when BIG-IP systems have rules in place that process HTTP response headers (Rapid7).

The exploitation of this vulnerability can result in a denial of service (DoS) attack and, in certain situations, may allow remote code execution (RCE), potentially leading to complete system compromise. The high CVSS score of 9.0 reflects the significant potential impact of this vulnerability (NVD, FortiGuard).

F5 has released patches to address this vulnerability in versions 16.0.1.1, 15.1.2.1, 14.1.4, 13.1.3.6, 12.1.5.3, and 11.6.5.3. Organizations are strongly advised to update their BIG-IP installations to these patched versions. The vulnerability was part of a larger security update that addressed multiple critical vulnerabilities in F5 products (Hacker News).