Apache HTTP Server contains a path traversal vulnerability that allows an attacker to perform remote code execution if files outside directories configured by Alias-like directives are not under default �require all denied� or if CGI scripts are enabled. The original patch issued under this CVE ID is insufficient, please review remediation information under CVE-2021-42013.

Apache HTTP Server contains a path traversal vulnerability that allows an attacker to perform remote code execution if files outside directories configured by Alias-like directives are not under default require all denied or if CGI scripts are enabled. This CVE ID resolves an incomplete patch for CVE-2021-41773.

A flaw was found in the Apache Log4j logging library 2.x. when the logging configuration uses a non-default Pattern Layout with a Context Lookup. Attackers with control over Thread Context Map (MDC) input data can craft malicious input data that contains a recursive lookup and can cause Denial of Service.

An out-of-bounds write in function apescapequotes of httpd allows an unauthenticated remote attacker to crash the server or potentially execute code on the system with the privileges of the httpd user, by providing malicious input to the function.

A flaw was found in Apache httpd in versions 2.4.32 to 2.4.46. The uwsgi protocol does not serialize more than 16K of HTTP header leading to resource exhaustion and denial of service. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

A heap overflow flaw was found In Apache httpd modsession. The highest threat from this vulnerability is to system availability.

In Apache Batik 1.x before 1.10, when deserializing subclass of AbstractDocument, the class takes a string from the inputStream as the class name which then use it to call the no-arg constructor of the class. Fix was to check the class type before calling newInstance in deserialization.

A website running in the InAppBrowser webview on Android could execute arbitrary JavaScript in the main application's webview using a specially crafted gap-iab: URI.

A buffer overflow flaw in httpd's lua module could allow an out-of-bounds write. An attacker who is able to submit a crafted request to an httpd instance that is using the lua module may be able to cause an impact to confidentiality, integrity, and/or availability.

A crafted request uri-path can cause modproxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.

Vulnerability in the Advanced Networking Option component of Oracle Database Server. Supported versions that are affected are 12.1.0.2, 12.2.0.1 and 19c. Difficult to exploit vulnerability allows unauthenticated attacker with network access via Oracle Net to compromise Advanced Networking Option. Successful attacks require human interaction from a person other than the attacker and while the vulnerability is in Advanced Networking Option, attacks may significantly impact additional products. Successful attacks of this vulnerability can result in takeover of Advanced Networking Option. Note: The July 2021 Critical Patch Update introduces a number of Native Network Encryption changes to deal with vulnerability CVE-2021-2351 and prevent the use of weaker ciphers. Customers should review: "Changes in Native Network Encryption with the July 2021 Critical Patch Update" (Doc ID 2791571.1). CVSS 3.1 Base Score 8.3 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H).

Apache Batik 1.13 is vulnerable to server-side request forgery, caused by improper input validation by the NodePickerPanel. By using a specially-crafted argument, an attacker could exploit this vulnerability to cause the underlying server to make arbitrary GET requests.

A crafted URI sent to httpd configured as a forward proxy (ProxyRequests on) can cause a crash (NULL pointer dereference) or, for configurations mixing forward and reverse proxy declarations, can allow for requests to be directed to a declared Unix Domain Socket endpoint (Server Side Request Forgery). This issue affects Apache HTTP Server 2.4.7 up to 2.4.51 (included).

Last updated 25 August 2025

Apache HTTP Server, with MPM event, worker or prefork, code executing in less-privileged child processes or threads (including scripts executed by an in-process scripting interpreter) could execute code with the privileges of the parent process (usually root) by manipulating the scoreboard.

It was discovered that the Tomcat packages installed configuration file /usr/lib/tmpfiles.d/tomcat.conf writeable to the tomcat group. A member of the group or a malicious web application deployed on Tomcat could use this flaw to escalate their privileges.

A flaw was found in Apache Tomcat, where the payload length in a WebSocket frame was not correctly validated. Invalid payload lengths could trigger an infinite loop. Multiple requests with invalid payload lengths could lead to a denial of service. The highest threat from this vulnerability is to system availability.

A carefully crafted request uri-path can cause modproxyuwsgi to read above the allocated memory and crash (DoS). This issue affects Apache HTTP Server versions 2.4.30 to 2.4.48 (inclusive).

A NULL pointer dereference in httpd allows an unauthenticated remote attacker to crash httpd by providing malformed HTTP requests. The highest threat from this vulnerability is to system availability.

A flaw was found in Apache Tomcat. When responding to new h2c connection requests, Apache Tomcat could duplicate request headers and a limited amount of request body from one request to another meaning user A and user B could both see the results of user A's request. The highest threat from this vulnerability is to data confidentiality.

A flaw was found in Apache Tomcat, where an h2c direct connection did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests are made, an OutOfMemoryException could occur, leading to a denial of service. The highest threat from this vulnerability is to system availability.

A flaw was found in Apache httpd in versions 2.4.20 to 2.4.43. Logging using the wrong pool by modhttp2 at debug/trace log level may lead to potential crashes and denial of service. The highest threat from this vulnerability is to system availability.

A null pointer de-reference was found in the way httpd handled specially crafted HTTP/2 request. A remote attacker could use this flaw to crash the httpd child process, causing temporary denial of service.

Apache Tomcat could allow a remote attacker to obtain sensitive information, caused by an issue when the HTTP request header value can be reused from the previous stream received on an HTTP/2 connection. By sending a specially-crafted HTTP request, an attacker could exploit this vulnerability to obtain sensitive information, and use this information to launch further attacks against the affected system.

While fuzzing the 2.4.49 httpd, a new null pointer dereference was detected during HTTP/2 request processing, allowing an external source to DoS the server. This requires a specially crafted request. The vulnerability was recently introduced in version 2.4.49. No exploit is known to the project.

Impact

When provided with a URL containing many @ characters in the authority component the authority regular expression exhibits catastrophic backtracking causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.

Patches

The issue has been fixed in urllib3 v1.26.5.

References

- CVE-2021-33503 - JVNVU#92413403 (English) - JVNVU#92413403 (Japanese) - urllib3 v1.26.5

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A NULL pointer dereference was found in Apache httpd modsession. The highest threat from this vulnerability is to system availability.

A flaw was found In Apache httpd. The modproxy has a NULL pointer dereference. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Apache HTTP Server versions 2.4.20 to 2.4.43. A specially crafted value for the 'Cache-Digest' header in a HTTP/2 request would result in a crash when the server actually tries to HTTP/2 PUSH a resource afterwards. Configuring the HTTP/2 feature via "H2Push off" will mitigate this vulnerability for unpatched servers.

Infinite loop in DVB-S2-BB dissector in Wireshark 3.4.0 to 3.4.5 allows denial of service via packet injection or crafted capture file