mod_ssl in Apache 2.0 up to 2.0.55, when configured with an SSL vhost with access control and a custom error 400 error page, allows remote attackers to cause a denial of service (application crash) via a non-SSL request to an SSL port, which triggers a NULL pointer dereference.

The byte-range filter in Apache 2.0 before 2.0.54 allows remote attackers to cause a denial of service (memory consumption) via an HTTP header with a large Range field.

The mod_ssl module in Apache 2.0.35 through 2.0.52, when using the "SSLCipherSuite" directive in directory or location context, allows remote clients to bypass intended restrictions by using any cipher suite that is allowed by the virtual host configuration.

The ap_get_mime_headers_core function in Apache httpd 2.0.49 allows remote attackers to cause a denial of service (memory exhaustion), and possibly an integer signedness error leading to a heap-based buffer overflow on 64 bit systems, via long header lines with large numbers of space or tab characters.

mod_disk_cache in Apache 2.0 through 2.0.49 stores client headers, including authentication information, on the hard disk, which could allow local users to gain sensitive information.