Buffer overflows in the ApacheBench benchmark support program (ab.c) in Apache before 1.3.27, and Apache 2.x before 2.0.43, allow a malicious web server to cause a denial of service and possibly execute arbitrary code via a long response.
The log files in Apache web server contain information directly supplied by clients and does not filter or quote control characters, which could allow remote attackers to hide HTTP requests and spoof source IP addresses when logs are viewed with UNIX programs such as cat, tail, and grep.