The Apache Xerces-C 3.0.0 to 3.2.3 XML parser contains a use-after-free error triggered during the scanning of external DTDs. This flaw has not been addressed in the maintained version of the library and has no current mitigation other than to disable DTD processing. This can be accomplished via the DOM using a standard parser feature, or via SAX using the XERCES_DISABLE_DTD environment variable.
Apache httpd allows remote attackers to read secret data from process memory if the Limit directive can be set in a user's .htaccess file, or if httpd.conf has certain misconfigurations, aka Optionsbleed. This affects the Apache HTTP Server through 2.2.34 and 2.4.x through 2.4.27. The attacker sends an unauthenticated OPTIONS HTTP request when attempting to read secret data. This is a use-after-free issue and thus secret data is not always sent, and the specific data depends on many factors including configuration. Exploitation with .htaccess can be blocked with a patch to the ap_limit_section function in server/core.c.
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.
A vulnerability was found in Apache HTTP Server 2.4.17 to 2.4.38. Using fuzzed network input, the http/2 request handling could be made to access freed memory in string comparison when determining the method of a request and thus process the request incorrectly.
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.
The Apache Xerces C++ XML parser on versions 3.0.0 before 3.2.5 contains a use-after-free error triggered during the scanning of external DTDs. Users are recommended to upgrade to version 3.2.5 which fixes the issue, or mitigate the issue by disabling DTD processing. This can be accomplished via the DOM using a standard parser feature, or via SAX using the XERCES_DISABLE_DTD environment variable. This issue has been disclosed before as CVE-2018-1311, but unfortunately that advisory incorrectly stated the issue would be fixed in version 3.2.3 or 3.2.4.
Use After Free vulnerability was discovered in fs/vfs/fs_rename code of the Apache NuttX RTOS, that due recursive implementation and single buffer use by two different pointer variables allowed arbitrary user provided size buffer reallocation and write to the previously freed heap chunk, that in specific cases could cause unintended virtual filesystem rename/move operation results. This issue affects Apache NuttX RTOS: from 7.20 before 12.11.0. Users of virtual filesystem based services with write access especially when exposed over the network (i.e. FTP) are affected and recommended to upgrade to version 12.11.0 that fixes the issue.
When under stress, closing many connections, the HTTP/2 handling code in Apache httpd 2.4.26 would sometimes access memory after it has been freed, resulting in potentially erratic behaviour.
Apache Guacamole 0.9.10 through 1.5.1 may continue to reference a freed RDP audio input buffer. Depending on timing, this may allow an attacker to execute arbitrary code with the privileges of the guacd process.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Versions of FreeRDP on the 3.x release branch before beta3 are subject to a Use-After-Free in processing `RDPGFX_CMDID_RESETGRAPHICS` packets. If `context->maxPlaneSize` is 0, `context->planesBuffer` will be freed. However, without updating `context->planesBuffer`, this leads to a Use-After-Free exploit vector. In most environments this should only result in a crash. This issue has been addressed in version 3.0.0-beta3 and users of the beta 3.x releases are advised to upgrade. There are no known workarounds for this vulnerability.