Apache Tomcat before 5.5.35, 6.x before 6.0.35, and 7.x before 7.0.23 computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters.

In Apache ORC 1.0.0 to 1.4.3 a malformed ORC file can trigger an endlessly recursive function call in the C++ or Java parser. The impact of this bug is most likely denial-of-service against software that uses the ORC file parser. With the C++ parser, the stack overflow might possibly corrupt the stack.

Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service. The attacker sends a stream of SETTINGS frames to the peer. Since the RFC requires that the peer reply with one acknowledgement per SETTINGS frame, an empty SETTINGS frame is almost equivalent in behavior to a ping. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both.

Apache Tomcat 5.5.0 to 5.5.11 allows remote attackers to cause a denial of service (CPU consumption) via a large number of simultaneous requests to list a web directory that has a large number of files.

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.

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.

When handling a libprocess message wrapped in an HTTP request, libprocess in Apache Mesos before 1.1.3, 1.2.x before 1.2.2, 1.3.x before 1.3.1, and 1.4.0-dev crashes if the request path is empty, because the parser assumes the request path always starts with '/'. A malicious actor can therefore cause a denial of service of Mesos masters rendering the Mesos-controlled cluster inoperable.

Format string vulnerability in LocalSyslogAppender in Apache log4net 1.2.9 might allow remote attackers to cause a denial of service (memory corruption and termination) via unknown vectors.

Unspecified vulnerability in (1) apreq_parse_headers and (2) apreq_parse_urlencoded functions in Apache2::Request (Libapreq2) before 2.07 allows remote attackers to cause a denial of service (CPU consumption) via unknown attack vectors that result in quadratic computational complexity.

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.

Off-by-one error in the mod_ssl Certificate Revocation List (CRL) verification callback in Apache, when configured to use a CRL, allows remote attackers to cause a denial of service (child process crash) via a CRL that causes a buffer overflow of one null byte.

Apache Tomcat before 5.x allows remote attackers to cause a denial of service (application crash) via a crafted AJP12 packet to TCP port 8007.

Apache SpamAssassin 3.0.1, 3.0.2, and 3.0.3 allows remote attackers to cause a denial of service (CPU consumption and slowdown) via a message with a long Content-Type header without any boundaries.

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.

The XML parser in Xerces-C++ 2.5.0 allows remote attackers to cause a denial of service (CPU consumption) via XML attributes in a crafted XML document.

A maliciously constructed HTTP/2 request could cause mod_http2 in Apache HTTP Server 2.4.24, 2.4.25 to dereference a NULL pointer and crash the server process.

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.

mod_ssl in Apache 2.0.50 and earlier allows remote attackers to cause a denial of service (CPU consumption) by aborting an SSL connection in a way that causes an Apache child process to enter an infinite loop.

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 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."

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.

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.

Unknown vulnerability in mod_python 2.7.9 allows remote attackers to cause a denial of service (httpd crash) via a certain query string, a variant of CAN-2003-0973.

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.

The prefork MPM in Apache 2 before 2.0.47 does not properly handle certain errors from accept, which could lead to a denial of service.

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.

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.

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 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.

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.

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.

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.

mod_dav in Apache before 2.0.42 does not properly handle versioning hooks, which may allow remote attackers to kill a child process via a null dereference and cause a denial of service (CPU consumption) in a preforked multi-processing module.

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).

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.

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.

Apache Tomcat 6.x before 6.0.37 and 7.x before 7.0.30 does not properly handle chunk extensions in chunked transfer coding, which allows remote attackers to cause a denial of service by streaming data.

When a client request to a cluster node was replicated to other nodes in the cluster for verification, the Content-Length was forwarded. On a DELETE request, the body was ignored, but if the initial request had a Content-Length value other than 0, the receiving nodes would wait for the body and eventually timeout. Mitigation: The fix to check DELETE requests and overwrite non-zero Content-Length header values was applied on the Apache NiFi 1.8.0 release. Users running a prior 1.x release should upgrade to the appropriate release.

In Apache HTTP server versions 2.4.37 and prior, by sending request bodies in a slow loris way to plain resources, the h2 stream for that request unnecessarily occupied a server thread cleaning up that incoming data. This affects only HTTP/2 (mod_http2) connections.

Certain input files could make the code to enter into an infinite loop when Apache Sanselan 0.97-incubator was used to parse them, which could be used in a DoS attack. Note that Apache Sanselan (incubating) was renamed to Apache Commons Imaging.

In Apache ShenYui, ShenYu-Bootstrap, RegexPredicateJudge.java uses Pattern.matches(conditionData.getParamValue(), realData) to make judgments, where both parameters are controllable by the user. This can cause an attacker pass in malicious regular expressions and characters causing a resource exhaustion. This issue affects Apache ShenYu (incubating) 2.4.0, 2.4.1 and 2.4.2 and is fixed in 2.4.3.

Apache DolphinScheduler user registration is vulnerable to Regular express Denial of Service (ReDoS) attacks, Apache DolphinScheduler users should upgrade to version 2.0.5 or higher.

In 0.9.3 or older versions of Apache Pinot segment upload path allowed segment directories to be imported into pinot tables. In pinot installations that allow open access to the controller a specially crafted request can potentially be exploited to cause disruption in pinot service. Pinot release 0.10.0 fixes this. See https://docs.pinot.apache.org/basics/releases/0.10.0

Subversion's mod_dav_svn is vulnerable to memory corruption. While looking up path-based authorization rules, mod_dav_svn servers may attempt to use memory which has already been freed. Affected Subversion mod_dav_svn servers 1.10.0 through 1.14.1 (inclusive). Servers that do not use mod_dav_svn are not affected.

In Apache ActiveMQ Artemis prior to 2.20.0 or 2.19.1, an attacker could partially disrupt availability (DoS) through uncontrolled resource consumption of memory.

A carefully crafted request body can cause a read to a random memory area which could cause the process to crash. This issue affects Apache HTTP Server 2.4.52 and earlier.

Adding method ACLs in remap.config can cause a segfault when the user makes a carefully crafted request. This affects versions Apache Traffic Server (ATS) 6.0.0 to 6.2.2 and 7.0.0 to 7.1.3. To resolve this issue users running 6.x should upgrade to 6.2.3 or later versions and 7.x users should upgrade to 7.1.4 or later versions.

By specially crafting HTTP/2 requests, workers would be allocated 60 seconds longer than necessary, leading to worker exhaustion and a denial of service. Fixed in Apache HTTP Server 2.4.34 (Affected 2.4.18-2.4.30,2.4.33).

The Apache Struts REST Plugin is using XStream library which is vulnerable and allow perform a DoS attack when using a malicious request with specially crafted XML payload. Upgrade to the Apache Struts version 2.5.16 and switch to an optional Jackson XML handler as described here http://struts.apache.org/plugins/rest/#custom-contenttypehandlers. Another option is to implement a custom XML handler based on the Jackson XML handler from the Apache Struts 2.5.16.