modaccess.c in lighttpd 1.4.15 ignores trailing / (slash) characters in the URL, which allows remote attackers to bypass url.access-deny settings.
Buffer overflow in the fcgienvadd function in modproxybackendfastcgi.c in the modfastcgi extension in lighttpd before 1.4.18 allows remote attackers to overwrite arbitrary CGI variables and execute arbitrary code via an HTTP request with a long content length, as demonstrated by overwriting the SCRIPTFILENAME variable, aka a "header overflow."
modauth (httpauth.c) in lighttpd before 1.4.16 allows remote attackers to cause a denial of service (daemon crash) via unspecified vectors involving (1) a memory leak, (2) use of md5-sess without a cnonce, (3) base64 encoded strings, and (4) trailing whitespace in the Auth-Digest header.
request.c in lighttpd 1.4.15 allows remote attackers to cause a denial of service (daemon crash) by sending an HTTP request with duplicate headers, as demonstrated by a request containing two Location header lines, which results in a segmentation fault.
lighttpd before 1.4.26, and 1.5.x, allocates a buffer for each read operation that occurs for a request, which allows remote attackers to cause a denial of service (memory consumption) by breaking a request into small pieces that are sent at a slow rate.
lighttpd 1.4.15, when run on 32 bit platforms, allows remote attackers to cause a denial of service (daemon crash) via unspecified vectors involving the use of incompatible format specifiers in certain debugging messages in the (1) modscgi, (2) modfastcgi, and (3) modwebdav modules.
connections.c in lighttpd before 1.4.16 might accept more connections than the configured maximum, which allows remote attackers to cause a denial of service (failed assertion) via a large number of connection attempts.
The configuration file for the FastCGI PHP support for lighttpd before 1.4.28 on Debian GNU/Linux creates a socket file with a predictable name in /tmp, which allows local users to hijack the PHP control socket and perform unauthorized actions such as forcing the use of a different version of PHP via a symlink attack or a race condition.