Apache HTTP Server protocol handler for the HTTP/2 protocol checks received request headers against the size limitations as configured for the server and used for the HTTP/1 protocol as well. On violation of these restrictions and HTTP response is sent to the client with a status code indicating why the request was rejected. This rejection response was not fully initialised in the HTTP/2 protocol handler if the offending header was the very first one received or appeared in a a footer. This led to a NULL pointer dereference on initialised memory, crashing reliably the child process. Since such a triggering HTTP/2 request is easy to craft and submit, this can be exploited to DoS the server. This issue affected mod_http2 1.15.17 and Apache HTTP Server version 2.4.47 only. Apache HTTP Server 2.4.47 was never released.

Improper Input Validation vulnerability in HTTP/2 of Apache Traffic Server allows an attacker to DOS the server. This issue affects Apache Traffic Server 7.0.0 to 7.1.12, 8.0.0 to 8.1.1, 9.0.0 to 9.0.1.

Apache webserver 2.0.52 and earlier allows remote attackers to cause a denial of service (CPU consumption) via an HTTP GET request with a MIME header containing multiple lines with a large number of space characters.

Apache mod_auth_radius 1.5.4 and libpam-radius-auth allow remote malicious RADIUS servers to cause a denial of service (crash) via a RADIUS_REPLY_MESSAGE with a RADIUS attribute length of 1, which leads to a memcpy operation with a -1 length argument.

A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service. An error introduced as part of a change to improve error handling during non-blocking I/O meant that the error flag associated with the Request object was not reset between requests. This meant that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users were able to trigger non-blocking I/O errors, e.g. by dropping a connection, thereby creating the possibility of triggering a DoS. Applications that do not use non-blocking I/O are not exposed to this vulnerability. This issue affects Apache Tomcat 10.0.3 to 10.0.4; 9.0.44; 8.5.64.

Apache 1.3.20 on Windows servers allows remote attackers to bypass the default index page and list directory contents via a URL with a large number of / (slash) characters.

The mod_dav_svn module for the Apache HTTP Server, as distributed in Apache Subversion before 1.6.17, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a request for a baselined WebDAV resource, as exploited in the wild in May 2011.

Off-by-one error in the XML signature feature in Apache XML Security for C++ 1.6.0, as used in Shibboleth before 2.4.3 and possibly other products, allows remote attackers to cause a denial of service (crash) via a signature using a large RSA key, which triggers a buffer overflow.

The mod_dav module in Apache 2.0.50 and earlier allows remote attackers to cause a denial of service (child process crash) via a certain sequence of LOCK requests for a location that allows WebDAV authoring access.

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."

The IPv6 URI parsing routines in the apr-util library for Apache 2.0.50 and earlier allow remote attackers to cause a denial of service (child process crash) via a certain URI, as demonstrated using the Codenomicon HTTP Test Tool.

Apache Tomcat 7.0.0 through 7.0.6 and 6.0.0 through 6.0.30 does not enforce the maxHttpHeaderSize limit for requests involving the NIO HTTP connector, which allows remote attackers to cause a denial of service (OutOfMemoryError) via a crafted request.

Unknown vulnerability in mod_python 3.0.x before 3.0.4, and 2.7.x before 2.7.9, allows remote attackers to cause a denial of service (httpd crash) via a certain query string.

Memory leak in ssl_engine_io.c for mod_ssl in Apache 2 before 2.0.49 allows remote attackers to cause a denial of service (memory consumption) via plain HTTP requests to the SSL port of an SSL-enabled server.

The Catalina org.apache.catalina.connector.http package in Tomcat 4.0.x up to 4.0.3 allows remote attackers to cause a denial of service via several requests that do not follow the HTTP protocol, which causes Tomcat to reject later requests.

Vulnerability in the apr_psprintf function in the Apache Portable Runtime (APR) library for Apache 2.0.37 through 2.0.45 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via long strings, as demonstrated using XML objects to mod_dav, and possibly other vectors.

If was found that the NetTest web service can be used to overload the bandwidth of a Apache OpenMeetings server. This issue was addressed in Apache OpenMeetings 6.0.0

Jakarta Tomcat before 3.3.1a on certain Windows systems may allow remote attackers to cause a denial of service (thread hang and resource consumption) via a request for a JSP page containing an MS-DOS device name, such as aux.jsp.

Unknown vulnerability in filestat.c for Apache running on OS2, versions 2.0 through 2.0.45, allows unknown attackers to cause a denial of service via requests related to device names.

Apache HTTP Server versions 2.4.0 to 2.4.46 A specially crafted Cookie header handled by mod_session can cause a NULL pointer dereference and crash, leading to a possible Denial Of Service

The authentication module for Apache 2.0.40 through 2.0.45 on Unix does not properly handle threads safely when using the crypt_r or crypt functions, which allows remote attackers to cause a denial of service (failed Basic authentication with valid usernames and passwords) when a threaded MPM is used.

A memory leak in Apache 2.0 through 2.0.44 allows remote attackers to cause a denial of service (memory consumption) via large chunks of linefeed characters, which causes Apache to allocate 80 bytes for each linefeed.

Apache 2 before 2.0.47, when running on an IPv6 host, allows attackers to cause a denial of service (CPU consumption by infinite loop) when the FTP proxy server fails to create an IPv6 socket.

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.

The servlet engine in Jakarta Apache Tomcat 3.3 and 4.0.4, when using IIS and the ajp1.3 connector, allows remote attackers to cause a denial of service (crash) via a large number of HTTP GET requests for an MS-DOS device such as AUX, LPT1, CON, or PRN.

mod_cgi in Apache 2.0.39 and 2.0.40 allows local users and possibly remote attackers to cause a denial of service (hang and memory consumption) by causing a CGI script to send a large amount of data to stderr, which results in a read/write deadlock between httpd and the CGI script.

Unknown vulnerability in Apache 1.3.19 running on HP Secure OS for Linux 1.0 allows remote attackers to cause "unexpected results" via an HTTP request.

Apache Tomcat 4.0.3, and possibly other versions before 4.1.3 beta, allows remote attackers to cause a denial of service (resource exhaustion) via a large number of requests to the server with null characters, which causes the working threads to hang.

The Java Server Pages (JSP) engine in Tomcat allows web page owners to cause a denial of service (engine crash) on the web server via a JSP page that calls WPrinterJob().pageSetup(null,null).

Apache POI in versions prior to release 3.17 are vulnerable to Denial of Service Attacks: 1) Infinite Loops while parsing crafted WMF, EMF, MSG and macros (POI bugs 61338 and 61294), and 2) Out of Memory Exceptions while parsing crafted DOC, PPT and XLS (POI bugs 52372 and 61295).

Apache with mod_rewrite enabled on most UNIX systems allows remote attackers to bypass RewriteRules by inserting extra / (slash) characters into the requested path, which causes the regular expression in the RewriteRule to fail.

Apache before 1.3.20 on Windows and OS/2 systems allows remote attackers to cause a denial of service (GPF) via an HTTP request for a URI that contains a large number of / (slash) or other characters, which causes certain functions to dereference a null pointer.

The ap_proxy_ajp_request function in mod_proxy_ajp.c in mod_proxy_ajp in the Apache HTTP Server 2.2.x before 2.2.15 does not properly handle certain situations in which a client sends no request body, which allows remote attackers to cause a denial of service (backend server outage) via a crafted request, related to use of a 500 error code instead of the appropriate 400 error code.

The Cluster::deliveredEvent function in cluster/Cluster.cpp in Apache Qpid, as used in Red Hat Enterprise MRG before 1.3 and other products, allows remote attackers to cause a denial of service (daemon crash and cluster outage) via invalid AMQP data.

The updatePosition function in lib/xmltok_impl.c in libexpat in Expat 2.0.1, as used in Python, PyXML, w3c-libwww, and other software, allows context-dependent attackers to cause a denial of service (application crash) via an XML document with crafted UTF-8 sequences that trigger a buffer over-read, a different vulnerability than CVE-2009-2625.

A DNS proxy and possible amplification attack vulnerability in WebClientInfo of Apache Wicket allows an attacker to trigger arbitrary DNS lookups from the server when the X-Forwarded-For header is not properly sanitized. This DNS lookup can be engineered to overload an internal DNS server or to slow down request processing of the Apache Wicket application causing a possible denial of service on either the internal infrastructure or the web application itself. This issue affects Apache Wicket Apache Wicket 9.x version 9.2.0 and prior versions; Apache Wicket 8.x version 8.11.0 and prior versions; Apache Wicket 7.x version 7.17.0 and prior versions and Apache Wicket 6.x version 6.2.0 and later versions.

XMLScanner.java in Apache Xerces2 Java, as used in Sun Java Runtime Environment (JRE) in JDK and JRE 6 before Update 15 and JDK and JRE 5.0 before Update 20, and in other products, allows remote attackers to cause a denial of service (infinite loop and application hang) via malformed XML input, as demonstrated by the Codenomicon XML fuzzing framework.

The Solaris pollset feature in the Event Port backend in poll/unix/port.c in the Apache Portable Runtime (APR) library before 1.3.9, as used in the Apache HTTP Server before 2.2.14 and other products, does not properly handle errors, which allows remote attackers to cause a denial of service (daemon hang) via unspecified HTTP requests, related to the prefork and event MPMs.

The expat XML parser in the apr_xml_* interface in xml/apr_xml.c in Apache APR-util before 1.3.7, as used in the mod_dav and mod_dav_svn modules in the Apache HTTP Server, allows remote attackers to cause a denial of service (memory consumption) via a crafted XML document containing a large number of nested entity references, as demonstrated by a PROPFIND request, a similar issue to CVE-2003-1564.

Apache ATS 6.0.0 to 6.2.3, 7.0.0 to 7.1.9, and 8.0.0 to 8.0.6 is vulnerable to a HTTP/2 slow read attack.

The Artofdefence Hyperguard Web Application Firewall (WAF) module before 2.5.5-11635, 3.0 before 3.0.3-11636, and 3.1 before 3.1.1-11637, a module for the Apache HTTP Server, allows remote attackers to cause a denial of service (memory consumption) via an HTTP request with a large Content-Length value but no POST data.

The streaming XML parser in Apache CXF 2.5.x before 2.5.10, 2.6.x before 2.6.7, and 2.7.x before 2.7.4 allows remote attackers to cause a denial of service (CPU and memory consumption) via crafted XML with a large number of (1) elements, (2) attributes, (3) nested constructs, and possibly other vectors.

cyrus-sasl (aka Cyrus SASL) 2.1.27 has an out-of-bounds write leading to unauthenticated remote denial-of-service in OpenLDAP via a malformed LDAP packet. The OpenLDAP crash is ultimately caused by an off-by-one error in _sasl_add_string in common.c in cyrus-sasl.

SQLite 3.30.1 mishandles certain SELECT statements with a nonexistent VIEW, leading to an application crash.

The default configuration of Apache ActiveMQ before 5.8.0 enables a sample web application, which allows remote attackers to cause a denial of service (broker resource consumption) via HTTP requests.

The ASN.1 parser in Bouncy Castle Crypto (aka BC Java) 1.63 can trigger a large attempted memory allocation, and resultant OutOfMemoryError error, via crafted ASN.1 data. This is fixed in 1.64.

The AsyncResponseWrapperImpl class in Apache Olingo versions 4.0.0 to 4.6.0 reads the Retry-After header and passes it to the Thread.sleep() method without any check. If a malicious server returns a huge value in the header, then it can help to implement a DoS attack.

A possible interaction between Apple MacOS X release 1.0 and Apache HTTP server allows remote attackers to cause a denial of service (crash) via a flood of HTTP GET requests to CGI programs, which generates a large number of processes.

An issue was discovered in the protobuf crate before 2.6.0 for Rust. Attackers can exhaust all memory via Vec::reserve calls.

internal/XMLReader.cpp in Apache Xerces-C before 3.1.2 allows remote attackers to cause a denial of service (segmentation fault and crash) via crafted XML data.