An unauthenticated remote attacker can send a crafted HTTP request containing an overly long SESSIONID cookie. This can trigger a stack buffer overflow in the modified lighttpd server, causing it to crash and potentially enabling remote code execution due to missing stack protections.

Improper length handling when parsing multiple cookie fields (including TRACKID) allows an unauthenticated remote attacker to send oversized cookie values and trigger a stack buffer overflow, resulting in a denial‑of‑service condition and possible remote code execution.

SQL injection vulnerability in modmysqlvhost.c in lighttpd before 1.4.35 allows remote attackers to execute arbitrary SQL commands via the host name, related to requestcheckhostname.

DISPUTED lighttpd before 1.4.54 has a signed integer overflow, which might allow remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a malicious HTTP GET request, as demonstrated by mishandling of /%2F? in burlnormalize2Ftoslashfix in burl.c. NOTE: The developer states "The feature which can be abused to cause the crash is a new feature in lighttpd 1.4.50, and is not enabled by default. It must be explicitly configured in the config file (e.g. lighttpd.conf). Certain input will trigger an abort() in lighttpd when that feature is enabled. lighttpd detects the underflow or realloc() will fail (in both 32-bit and 64-bit executables), also detected in lighttpd. Either triggers an explicit abort() by lighttpd. This is not exploitable beyond triggering the explicit abort() with subsequent application exit."

lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing. This behavior can be exploited to conduct HTTP Header Smuggling attacks.

Successful exploitation may allow an attacker to:

Bypass access control rules Inject unsafe input into backend logic that trusts request headers Execute HTTP Request Smuggling attacks under some conditions

This issue affects lighttpd1.4.80

modaccess.c in lighttpd 1.4.15 ignores trailing / (slash) characters in the URL, which allows remote attackers to bypass url.access-deny settings.

lighttpd before 1.4.14 allows attackers to cause a denial of service (crash) via a request to a file whose mtime is 0, which results in a NULL pointer dereference.

The device exposes a web interface on ports TCP/3030 and TCP/9882. This web service runs lighttpd, which implements the “SNORE” interface. This interface is affected by a stack buffer overflow vulnerability due to insecure path parsing. An attacker with access to the LAN network interface could use a specially crafted HTTP request to exploit a buffer overflow on the modem.

lighttpd before 1.4.33 does not check the return value of the (1) setuid, (2) setgid, or (3) setgroups functions, which might cause lighttpd to run as root if it is restarted and allows remote attackers to gain privileges, as demonstrated by multiple calls to the clone function that cause setuid to fail when the user process limit is reached.

lighttpd before 1.4.34, when SNI is enabled, configures weak SSL ciphers, which makes it easier for remote attackers to hijack sessions by inserting packets into the client-server data stream or obtain sensitive information by sniffing the network.

modauth in lighttpd before 1.4.36 allows remote attackers to inject arbitrary log entries via a basic HTTP authentication string without a colon character, as demonstrated by a string containing a NULL and new line character.

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.

moduserdir 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.

An issue was discovered in modaliasphysicalhandler in modalias.c in lighttpd before 1.4.50. There is potential ../ path traversal of a single directory above an alias target, with a specific modalias configuration where the matched alias lacks a trailing '/' character, but the alias target filesystem path does have a trailing '/' character.

In lighttpd 1.4.65, modwstunnel does not initialize a handler function pointer if an invalid HTTP request (websocket handshake) is received. It leads to null pointer dereference which crashes the server. It could be used by an external attacker to cause denial of service condition.

A resource leak in gwbackend.c in lighttpd 1.4.56 through 1.4.66 could lead to a denial of service (connection-slot exhaustion) after a large amount of anomalous TCP behavior by clients. It is related to RDHUP mishandling in certain HTTP/1.1 chunked situations. Use of modfastcgi is, for example, affected. This is fixed in 1.4.67.

Lighttpd 1.4.56 through 1.4.58 allows a remote attacker to cause a denial of service (CPU consumption from stuck connections) because connectionreadheadermore in connections.c has a typo that disrupts use of multiple read operations on large headers.

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.

In lighttpd 1.4.46 through 1.4.63, the modextforwardForwarded function of the modextforward plugin has a stack-based buffer overflow (4 bytes representing -1), as demonstrated by remote denial of service (daemon crash) in a non-default configuration. The non-default configuration requires handling of the Forwarded header in a somewhat unusual manner. Also, a 32-bit system is much more likely to be affected than a 64-bit system.

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.

There exists use-after-free vulnerabilities in lighttpd <= 1.4.50 request parsing which might read from invalid pointers to memory used in the same request, not from other requests.

The bufferurldecode function in Lighttpd 1.3.7 and earlier does not properly handle control characters, which allows remote attackers to obtain the source code for CGI and FastCGI scripts via a URL with a %00 (null) character after the file extension.

response.c in Lighttpd 1.4.10 and possibly previous versions, when run on Windows, allows remote attackers to read arbitrary source code via requests that contain trailing (1) "." (dot) and (2) space characters, which are ignored by Windows, as demonstrated by PHP files.

The httprequestsplitvalue function in request.c in lighttpd before 1.4.32 allows remote attackers to cause a denial of service (infinite loop) via a request with a header containing an empty token, as demonstrated using the "Connection: TE,,Keep-Alive" header.

Use-after-free vulnerability in lighttpd before 1.4.33 allows remote attackers to cause a denial of service (segmentation fault and crash) via unspecified vectors that trigger FAMMonitorDirectory failures.

Multiple directory traversal vulnerabilities in (1) modevhost and (2) modsimplevhost in lighttpd before 1.4.35 allow remote attackers to read arbitrary files via a .. (dot dot) in the host name, related to requestcheckhostname.

lighttpd 1.4.12 and 1.4.13 allows remote attackers to cause a denial of service (cpu and resource consumption) by disconnecting while lighttpd is parsing CRLF sequences, which triggers an infinite loop and file descriptor consumption.

An signedness error, leading to out of stack-based buffer read flaw was found in the way lighttpd, a lightning fast webserver with light system requirements, processed certain invalid base64 HTTP authentication tokens. A remote attacker could provide a specially crafted HTTP authentication request, leading to denial of service (lighttpd daemon crash due to an signedness error while processing the token).

Upstream bug report: [1] http://redmine.lighttpd.net/issues/2370

Upstream patch (with testcase and NEWS update): [2] http://redmine.lighttpd.net/projects/lighttpd/repository/revisions/2806/diff

References: [3] http://download.lighttpd.net/lighttpd/security/lighttpdsa201101.txt (upstream advisory) [4] http://www.openwall.com/lists/oss-security/2011/11/29/8 (CVE request) [5] http://www.openwall.com/lists/oss-security/2011/11/29/13 (CVE assignment)

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.