The 'sosreport' program, part of the ABRT bug reporting system used in Red Hat Enterprise Linux, does not handle symbolic links correctly when writing core dumps of ABRT programs to the ABRT dump directory (/var/tmp/abrt). This can be leveraged by local unprivileged attackers to gain root privileges on vulnerable systems.
The 'fusermount' binary, part of the FUSE system in Linux, executes the /bin/mount binary with ruid set to 0 without clearing the environment variables provided by unprivileged users. This flaw can be leveraged by local unprivileged users to gain root privileges by leveraging the functionality provided by the LIBMOUNT_MTAB environment variable to overwrite an arbitrary file on the affected system. This module will try to overwrite the /etc/bash.bashrc file, which is executed every time any user spawns an interactive Bash shell. That means that a new agent will be deployed every time any user opens a new interactive shell (either login or non-login ones) on the vulnerable machine. Note that this also means that installed agents will run with the privileges of the users that have launched interactive shells. Unlike other privilege escalation exploits, this module will not stop after installing the first agent; it will stay running until a new agent with root permissions is installed (that is, if the root user happens to run an interactive shell on the vulnerable machine), or until the user-specified time limit is reached, whatever happens first. Note that non-root agents will be kept, since they still can be valuable despite not having superuser privileges.
An elevation of privilege vulnerability exists when Windows kernel does not properly constrain impersonation levels. The vulnerability occurs because a user can place symlinks for the system drives in the per-login session device map and the kernel will follow them during impersonation. An attacker who successfully exploited this vulnerability may, for example, redirect a call to LoadLibrary, from a system service (when impersonating), to an arbitrary location.
FortiClient is prone to a privilege-escalation vulnerability that affects mdare64_48.sys, mdare32_48.sys, mdare32_52.sys, mdare64_52.sys and Fortishield.sys drivers. All these drivers expose an API to manage processes and the windows registry, for instance, the IOCTL 0x2220c8 of the mdareXX_XX.sys driver returns a full privileged handle to a given process PID. In particular, this same function is replicated inside Fortishield.sys. Attackers can leverage this issue to execute arbitrary code with elevated privileges in the context of any selected process. This module uses the previous vulnerability to inject an agent inside lsass.exe process.
An elevation of privilege vulnerability exists when the Win32k.sys kernel-mode driver improperly handles objects in memory. The vulnerability exists in the Windows OS process of creating windows for applications. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. This module exploits the previous vulnerability to deploy an agent that runs with SYSTEM privileges.
An elevation of privilege vulnerability exists in the Windows kernel-mode driver (Win32k.sys) that is caused when it improperly handles objects in memory. A local unprivileged user who successfully exploited this vulnerability could execute arbitrary code with SYSTEM privileges. This module exploits the previous vulnerability to deploy an agent that runs with SYSTEM privileges.
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