PHP 4.3.4 and earlier in Apache 1.x and 2.x (mod_php) can leak global variables between virtual hosts that are handled by the same Apache child process but have different settings, which could allow remote attackers to obtain sensitive information.
Heap-based buffer overflow in proxy_util.c for mod_proxy in Apache 1.3.25 to 1.3.31 allows remote attackers to cause a denial of service (process crash) and possibly execute arbitrary code via a negative Content-Length HTTP header field, which causes a large amount of data to be copied.
Apache 1.4.x before 1.3.30, and 2.0.x before 2.0.49, when using multiple listening sockets on certain platforms, allows remote attackers to cause a denial of service (blocked new connections) via a "short-lived connection on a rarely-accessed listening socket."
mod_access in Apache 1.3 before 1.3.30, when running big-endian 64-bit platforms, does not properly parse Allow/Deny rules using IP addresses without a netmask, which could allow remote attackers to bypass intended access restrictions.
mod_digest_apple for Apache 1.3.31 and 1.3.32 on Mac OS X Server does not properly verify the nonce of a client response, which allows remote attackers to replay credentials.
Apache HTTP Server 1.3.22 through 1.3.27 on OpenBSD allows remote attackers to obtain sensitive information via (1) the ETag header, which reveals the inode number, or (2) multipart MIME boundary, which reveals child process IDs (PID).
Multiple stack-based buffer overflows in (1) mod_alias and (2) mod_rewrite for Apache before 1.3.29 allow attackers to create configuration files to cause a denial of service (crash) or execute arbitrary code via a regular expression with more than 9 captures.
The rotatelogs program on Apache before 1.3.28, for Windows and OS/2 systems, does not properly ignore certain control characters that are received over the pipe, which could allow remote attackers to cause a denial of service.
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.