mod_userdir in lighttpd before 1.4.20, when a case-insensitive operating system or filesystem is used, performs case-sensitive comparisons on filename components in configuration options, which might allow remote attackers to bypass intended access restrictions, as demonstrated by a request for a .PHP file when there is a configuration rule for .php files. (CVSS:7.8) (Last Update:2009-02-26)

lighttpd before 1.4.20 compares URIs to patterns in the (1) url.redirect and (2) url.rewrite configuration settings before performing URL decoding, which might allow remote attackers to bypass intended access restrictions, and obtain sensitive information or possibly modify data. (CVSS:7.5) (Last Update:2009-02-26)

Memory leak in the http_request_parse function in request.c in lighttpd before 1.4.20 allows remote attackers to cause a denial of service (memory consumption) via a large number of requests with duplicate request headers. (CVSS:5.0) (Last Update:2009-02-26)

The connection_state_machine function (connections.c) in lighttpd 1.4.19 and earlier, and 1.5.x before 1.5.0, allows remote attackers to cause a denial of service (active SSL connection loss) by triggering an SSL error, such as disconnecting before a download has finished, which causes all active SSL connections to be lost. (CVSS:4.3) (Last Update:2011-10-11)

mod_userdir in lighttpd 1.4.18 and earlier, when userdir.path is not set, uses a default of $HOME, which might allow remote attackers to read arbitrary files, as demonstrated by accessing the ~nobody directory. (CVSS:5.0) (Last Update:2008-09-05)

mod_cgi in lighttpd 1.4.18 sends the source code of CGI scripts instead of a 500 error when a fork failure occurs, which might allow remote attackers to obtain sensitive information. (CVSS:5.0) (Last Update:2011-09-21)

lighttpd 1.4.18, and possibly other versions before 1.5.0, does not properly calculate the size of a file descriptor array, which allows remote attackers to cause a denial of service (crash) via a large number of connections, which triggers an out-of-bounds access. (CVSS:5.0) (Last Update:2008-09-10)

Buffer overflow in the fcgi_env_add function in mod_proxy_backend_fastcgi.c in the mod_fastcgi 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 SCRIPT_FILENAME variable, aka a “header overflow.” (CVSS:6.8) (Last Update:2008-09-05)

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. (CVSS:5.8) (Last Update:2012-10-30)

mod_auth (http_auth.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. (CVSS:6.4) (Last Update:2012-10-30)