Apache does not filter terminal escape sequences from its error logs, which could make it easier for attackers to insert those sequences into terminal emulators containing vulnerabilities related to escape sequences.

Buffer overflow in htdigest in Apache 1.3.26 and 1.3.27 may allow attackers to execute arbitrary code via a long user argument. NOTE: since htdigest is normally only locally accessible and not setuid or setgid, there are few attack vectors which would lead to an escalation of privileges, unless htdigest is executed from a CGI program. Therefore this may not be a vulnerability.

The shared memory scoreboard in the HTTP daemon for Apache 1.3.x before 1.3.27 allows any user running as the Apache UID to send a SIGUSR1 signal to any process as root, resulting in a denial of service (process kill) or possibly other behaviors that would not normally be allowed, by modifying the parent[].pid and parent[].last_rtime segments in the scoreboard.

Cross-site scripting (XSS) vulnerability in the default error page of Apache 2.0 before 2.0.43, and 1.3.x up to 1.3.26, when UseCanonicalName is "Off" and support for wildcard DNS is present, allows remote attackers to execute script as other web page visitors via the Host: header, a different vulnerability than CAN-2002-1157.

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.

Apache 1.3 through 1.3.24, and Apache 2.0 through 2.0.36, allows remote attackers to cause a denial of service and possibly execute arbitrary code via a chunk-encoded HTTP request that causes Apache to use an incorrect size.

Apache for Win32 before 1.3.24, and 2.0.x before 2.0.34-beta, allows remote attackers to execute arbitrary commands via shell metacharacters (a | pipe character) provided as arguments to batch (.bat) or .cmd scripts, which are sent unfiltered to the shell interpreter, typically cmd.exe.

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.

The default installation of Apache before 1.3.19 on Mandrake Linux 7.1 through 8.0 and Linux Corporate Server 1.0.1 allows remote attackers to list the directory index of arbitrary web directories.

Cross site scripting vulnerabilities in Apache 1.3.0 through 1.3.11 allow remote attackers to execute script as other web site visitors via (1) the printenv CGI (printenv.pl), which does not encode its output, (2) pages generated by the ap_send_error_response function such as a default 404, which does not add an explicit charset, or (3) various messages that are generated by certain Apache modules or core code. NOTE: the printenv issue might still exist for web browsers that can render text/plain content types as HTML, such as Internet Explorer, but CVE regards this as a design limitation of those browsers, not Apache. The printenv.pl/acuparam vector, discloser on 20070724, is one such variant.