In versions of Apache CXF before 3.6.4 and 4.0.5 (3.5.x and lower versions are not impacted), a CXF HTTP client conduit may prevent HTTPClient instances from being garbage collected and it is possible that memory consumption will continue to increase, eventually causing the application to run out of memory

An h2c direct connection to Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36 and 8.5.1 to 8.5.56 did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests were made, an OutOfMemoryException could occur leading to a denial of service.

ActionForm in Apache Software Foundation (ASF) Struts before 1.2.9 with BeanUtils 1.7 allows remote attackers to cause a denial of service via a multipart/form-data encoded form with a parameter name that references the public getMultipartRequestHandler method, which provides further access to elements in the CommonsMultipartRequestHandler implementation and BeanUtils.

handler/ssl/OpenSslEngine.java in Netty 4.0.x before 4.0.37.Final and 4.1.x before 4.1.1.Final allows remote attackers to cause a denial of service (infinite loop).

Improper Input Validation vulnerability in Apache Tomcat. Incorrect error handling for some invalid HTTP priority headers resulted in incomplete clean-up of the failed request which created a memory leak. A large number of such requests could trigger an OutOfMemoryException resulting in a denial of service. This issue affects Apache Tomcat: from 9.0.76 through 9.0.102, from 10.1.10 through 10.1.39, from 11.0.0-M2 through 11.0.5. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.90 though 8.5.100. Users are recommended to upgrade to version 9.0.104, 10.1.40 or 11.0.6 which fix the issue.

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."

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.

mod_auth_openidc is an authentication/authorization module for the Apache 2.x HTTP server that functions as an OpenID Connect Relying Party, authenticating users against an OpenID Connect Provider. When mod_auth_openidc versions prior to 2.4.9 are configured to use an unencrypted Redis cache (`OIDCCacheEncrypt off`, `OIDCSessionType server-cache`, `OIDCCacheType redis`), `mod_auth_openidc` wrongly performed argument interpolation before passing Redis requests to `hiredis`, which would perform it again and lead to an uncontrolled format string bug. Initial assessment shows that this bug does not appear to allow gaining arbitrary code execution, but can reliably provoke a denial of service by repeatedly crashing the Apache workers. This bug has been corrected in version 2.4.9 by performing argument interpolation only once, using the `hiredis` API. As a workaround, this vulnerability can be mitigated by setting `OIDCCacheEncrypt` to `on`, as cache keys are cryptographically hashed before use when this option is enabled.

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.

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ. During unmarshalling of OpenWire commands the size value of buffers was not properly validated which could lead to excessive memory allocation and be exploited to cause a denial of service (DoS) by depleting process memory, thereby affecting applications and services that rely on the availability of the ActiveMQ broker when not using mutual TLS connections. This issue affects Apache ActiveMQ: from 6.0.0 before 6.1.6, from 5.18.0 before 5.18.7, from 5.17.0 before 5.17.7, before 5.16.8. ActiveMQ 5.19.0 is not affected. Users are recommended to upgrade to version 6.1.6+, 5.19.0+, 5.18.7+, 5.17.7, or 5.16.8 or which fixes the issue. Existing users may implement mutual TLS to mitigate the risk on affected brokers.

In CVE-2023-25194, we announced the RCE/Denial of service attack via SASL JAAS JndiLoginModule configuration in Kafka Connect API. But not only Kafka Connect API is vulnerable to this attack, the Apache Kafka brokers also have this vulnerability. To exploit this vulnerability, the attacker needs to be able to connect to the Kafka cluster and have the AlterConfigs permission on the cluster resource. Since Apache Kafka 3.4.0, we have added a system property ("-Dorg.apache.kafka.disallowed.login.modules") to disable the problematic login modules usage in SASL JAAS configuration. Also by default "com.sun.security.auth.module.JndiLoginModule" is disabled in Apache Kafka 3.4.0, and "com.sun.security.auth.module.JndiLoginModule,com.sun.security.auth.module.LdapLoginModule" is disabled by default in in Apache Kafka 3.9.1/4.0.0

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.

Allocation of Resources Without Limits or Throttling vulnerability in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.7, from 10.1.0-M1 through 10.1.41, from 9.0.0.M1 through 9.0.105. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 though 8.5.100. Other, older, EOL versions may also be affected. Users are recommended to upgrade to version 11.0.8, 10.1.42 or 9.0.106, which fix the issue.

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.

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

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

Improper Input Validation vulnerability in Apache Kvrocks. The SETRANGE command didn't check if the `offset` input is a positive integer and use it as an index of a string. So it will cause the server to crash due to its index is  out of range. This issue affects Apache Kvrocks: through 2.11.1. Users are recommended to upgrade to version 2.12.0, which fixes the issue.

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.

XStream is a Java library to serialize objects to XML and back again. In XStream before version 1.4.16, there is vulnerability which may allow a remote attacker to allocate 100% CPU time on the target system depending on CPU type or parallel execution of such a payload resulting in a denial of service only by manipulating the processed input stream. No user is affected who followed the recommendation to setup XStream's security framework with a whitelist limited to the minimal required types. If you rely on XStream's default blacklist of the Security Framework, you will have to use at least version 1.4.16.

Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability in Apache NimBLE.  Specially crafted GATT operation can cause infinite loop in GATT server leading to denial of service in Bluetooth stack or device. This issue affects Apache NimBLE: through 1.6.0. Users are recommended to upgrade to version 1.7.0, which fixes the issue.

Denial of Service due to improper input validation vulnerability for HTTP/2 requests in Apache Tomcat. When processing an HTTP/2 request, if the request exceeded any of the configured limits for headers, the associated HTTP/2 stream was not reset until after all of the headers had been processed.This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.0-M16, from 10.1.0-M1 through 10.1.18, from 9.0.0-M1 through 9.0.85, from 8.5.0 through 8.5.98. Other, older, EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M17, 10.1.19, 9.0.86 or 8.5.99 which fix the issue.

Attackers can use public NetTest web service of Apache OpenMeetings 4.0.0-5.0.0 to organize denial of service attack.

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).

It was found that when Artemis and HornetQ before 2.4.0 are configured with UDP discovery and JGroups discovery a huge byte array is created when receiving an unexpected multicast message. This may result in a heap memory exhaustion, full GC, or OutOfMemoryError.

A potential denial of service vulnerability is present in versions of Apache CXF before 3.5.10, 3.6.5 and 4.0.6. In some edge cases, the CachedOutputStream instances may not be closed and, if backed by temporary files, may fill up the file system (it applies to servers and clients).

Improper Authentication vulnerability in Apache Pulsar WebSocket Proxy allows an attacker to connect to the /pingpong endpoint without authentication. This issue affects Apache Pulsar WebSocket Proxy: from 2.8.0 through 2.8.*, from 2.9.0 through 2.9.*, from 2.10.0 through 2.10.4, from 2.11.0 through 2.11.1, 3.0.0. The known risks include a denial of service due to the WebSocket Proxy accepting any connections, and excessive data transfer due to misuse of the WebSocket ping/pong feature. 2.10 Pulsar WebSocket Proxy users should upgrade to at least 2.10.5. 2.11 Pulsar WebSocket Proxy users should upgrade to at least 2.11.2. 3.0 Pulsar WebSocket Proxy users should upgrade to at least 3.0.1. 3.1 Pulsar WebSocket Proxy users are unaffected. Any users running the Pulsar WebSocket Proxy for 2.8, 2.9, and earlier should upgrade to one of the above patched versions.

Allocation of resources without limits or throttling in the HTTP/2 HPACK decoder in Apache HttpComponents Core (5.4.2 and earlier, 5.5-beta1 and earlier) allows an remote attacker to cause a denial of service through memory exhaustion by sending oversized compressed header blocks before the HTTP/2 SETTINGS acknowledgement causes the configured header list size limit to be applied.

Uncontrolled Resource Consumption vulnerability in the HTTP/1.1 message parser in Apache HttpComponents Core (5.4.2 and earlier, 5.5-beta1 and earlier) allows an remote attacker to cause a denial of service through memory exhaustion by sending messages with excessive number of headers / excessive header length

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ Stomp. An unauthenticated client that opens a STOMP NIO connection can send header bytes that never terminate which makes the broker buffer them without limit, exhausting the JVM heap. This issue affects Apache ActiveMQ: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ All: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ Stomp: before 5.19.8, from 6.0.0 before 6.2.7. Users are recommended to upgrade to version 6.2.7 or 5.19.8, which fixes the issue.

In Apache NiFi 1.0.0 to 1.11.4, the NiFi download token (one-time password) mechanism used a fixed cache size and did not authenticate a request to create a download token, only when attempting to use the token to access the content. An unauthenticated user could repeatedly request download tokens, preventing legitimate users from requesting download tokens.

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All. An unauthenticated network attacker can cause a broker DoS by sending a crafted WireFormatInfo frame with a malicious large size value. The value is not validate and causes the broker to attempt allocation during pre-auth negotiation which can trigger OOM and crash the broker. This issue affects Apache ActiveMQ Client: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ All: before 5.19.8, from 6.0.0 before 6.2.7. Users are recommended to upgrade to version 6.2.7 or 5.19.8, which fixes the issue.

Denial of Service via Out of Memory vulnerability in Apache ActiveMQ Broker, Apache ActiveMQ, Apache ActiveMQ All. Following the fix for CVE-2026-49270 an unauthenticated attacker can now cause broker OOM by sending an repeated BrokerInfo commands without sending a ConnectionInfo, until the broker will crash with OOM. This issue affects Apache ActiveMQ Broker: from 5.19.7 before 5.19.8, from 6.2.6 before 6.2.7; Apache ActiveMQ: from 5.19.7 before 5.19.8, from 6.2.6 before 6.2.7; Apache ActiveMQ All: from 5.19.7 before 5.19.8, from 6.2.6 before 6.2.7. Users are recommended to upgrade to version 6.2.7, which fixes the issue.

qpid-cpp: ACL policies only loaded if the acl-file option specified enabling DoS by consuming all available file descriptors

Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads to denial of service via malicious HTTP requests. This issue affects Apache HTTP Server: from 2.4.17 through 2.4.67.

There is no restriction on the amount of attachment headers that a message can contain when being deserialized by Apache CXF, which can lead to uncontrolled resource consumption or a denial of service attack. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fix this issue by imposing a maximum default of 500 attachments per message.

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

Improper Input Validation vulnerability in Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ Stomp. A remote unauthenticated peer that can reach an exposed STOMP connector can trigger denial-of-service behavior by sending a negative content-length. For the NIO STOMP transport, an attacker can keep streaming body bytes and grow the per-connection command buffer beyond configured limits to cause OOM. For the blocking STOMP protocol, an error will instead force abnormal transport exception handling for the affected connection and closure. This issue affects Apache ActiveMQ: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ All: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ Stomp: before 5.19.8, from 6.0.0 before 6.2.7. Users are recommended to upgrade to version 6.2.7 or 5.19.8, which fixes the issue.

An attacker, opening a HTTP/2 connection with an initial window size of 0, was able to block handling of that connection indefinitely in Apache HTTP Server. This could be used to exhaust worker resources in the server, similar to the well known "slow loris" attack pattern. This has been fixed in version 2.4.58, so that such connection are terminated properly after the configured connection timeout. This issue affects Apache HTTP Server: from 2.4.55 through 2.4.57. Users are recommended to upgrade to version 2.4.58, which fixes the issue.

When a Multipart request is performed but some of the fields exceed the maxStringLength  limit, the upload files will remain in struts.multipart.saveDir  even if the request has been denied. Users are recommended to upgrade to versions Struts 2.5.32 or 6.1.2.2 or Struts 6.3.0.1 or greater, which fixe this issue.

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

Improper Input Validation vulnerability in Apache Traffic Server with malformed HTTP/2 frames.This issue affects Apache Traffic Server: from 9.0.0 through 9.2.2. Users are recommended to upgrade to version 9.2.3, which fixes the issue.

Memory Allocation with Excessive Size Value vulnerability in Apache Thrift. This issue affects Apache Thrift: before 0.23.0. Users are recommended to upgrade to version 0.23.0, which fixes the issue.

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.

OOM Denial of Service via Unbounded Array Allocation in Apache OpenNLP AbstractModelReader  Versions Affected:  before 1.9.5 before 2.5.9 before 3.0.0-M3  Description: The AbstractModelReader methods getOutcomes(), getOutcomePatterns(), and getPredicates() each read a 32-bit signed integer count field from a binary model stream and pass that value directly to an array allocation (new String[numOutcomes], new int[numOCTypes][], new String[NUM_PREDS]) without validating that the value is non-negative or within a reasonable bound. The count is therefore fully attacker-controlled when the model file originates from an untrusted source. A crafted .bin model file in which any of these count fields is set to Integer.MAX_VALUE (or any value large enough to exhaust the available heap) triggers an OutOfMemoryError at the array allocation itself, before the corresponding label or pattern data is consumed from the stream. The error occurs very early in deserialization: for a GIS model, getOutcomes() is reached after only the model-type string, the correction constant, and the correction parameter have been read; so the attacker pays no meaningful size cost to weaponize a payload, and a single small file can crash a JVM that loads it. Any code path that deserializes a .bin model is affected, including direct use of GenericModelReader and any higher-level component that delegates to it during model load. The practical impact is denial of service against processes that load model files from untrusted or semi-trusted origins.   Mitigation: * 2.x users should upgrade to 2.5.9. * 3.x users should upgrade to 3.0.0-M3. Note: The fix introduces an upper bound on each of the three count fields, checked before array allocation; counts that are negative or exceed the bound cause an IllegalArgumentException to be thrown and the read to fail fast with no large allocation. The default bound is 10,000,000, which is well above the entry counts of legitimate OpenNLP models but far below any value that would threaten heap exhaustion. Deployments that legitimately need to load models with more entries than the default can raise the limit at JVM startup by setting the OPENNLP_MAX_ENTRIES system property to the desired positive integer (e.g. -DOPENNLP_MAX_ENTRIES=50000000); invalid or non-positive values fall back to the default. Users who cannot upgrade immediately should treat all .bin model files as untrusted input unless their provenance is verified, and should avoid loading models supplied by end users or fetched from third-party repositories without integrity checks.

Apache Neethi does not properly detect circular references in policy definitions. When a WS-Policy document contains circular policy references (where Policy A references Policy B which references Policy A), the policy normalization process can enter an infinite loop or cause excessive recursion, leading to a stack overflow or application hang. An attacker can craft malicious policy documents with circular references to cause a Denial of Service condition Users are recommended to upgrade to version 3.2.2, which fixes this issue.

Heap-based Buffer Overflow vulnerability in Apache HTTP Server with mod_xml2enc, xml2StartParse, and untrusted content This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.

Apache Neethi is vulnerable to a Denial of Service attack through algorithmic complexity in policy normalization. Specially crafted WS-Policy documents can trigger an exponential Cartesian cross-product expansion during the normalization process, causing unbounded memory allocation that exhausts the JVM heap. This occurs when the normalization process generates an excessive number of policy alternatives without bounds, leading to runtime memory exhaustion. Users should upgrade to 3.2.2 which limits the maximum number of normalized policy alternatives.

Apache IoTDB version 0.12.2 to 0.12.6, 0.13.0 to 0.13.2 are vulnerable to a Denial of Service attack when accepting untrusted patterns for REGEXP queries with Java 8. Users should upgrade to 0.13.3 which addresses this issue or use a later version of Java to avoid it.

Allocation of Resources Without Limits or Throttling vulnerability in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117. Older, unsupported versions may also be affected. Users are recommended to upgrade to version [FIXED_VERSION], which fixes the issue.