SSD Advisory – VirtualBox VRDP Guest-to-Host Escape

Vulnerability Summary
VirtualBox has a built-in RDP server which provides access to a guest machine. While the RDP client sees the guest OS, the RDP server runs on the host OS. Therefore, to view the guest OS the RDP client will make a connection to the host OS IP address rather than the guest OS IP address.

The VRDP server is composted of two parts: a high level, which is open source and residing in the VirtualBox source tree, and is responsible for the display management, and a low level shipped with Extension Pack which is the RDP server which conforms to RDP specifications.

The vulnerability is in the high level part. The vulnerability can be triggered when a connection to a Windows guest OS is closed, i.e. when we close the window of the RDP client application like rdesktop or Microsoft Remote Desktop.

While the crashing bug was reported to the VirtualBox tracker (https://www.virtualbox.org/ticket/16444), it was never considered a security vulnerability, and is not marked as one. This ticket is 15 months old at the time of writing this post and still marked as unresolved.

Prerequisites to exploit the vulnerability:

  • VirtualBox Extension Pack installed on a host. It’s required to enable VRDP server
  • VRDP server enabled
  • 3D acceleration enabled
  • Windows 10 as a guest

The vulnerability can probably be triggered from other guest OS due to the fact the the vulnerable code resides inside the Guest Additions driver.

Credit
An independent security researcher, Sergey Zelenyuk, has reported this vulnerability to Beyond Security’s SecuriTeam Secure Disclosure program.
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SSD Advisory – Linux Kernel AF_PACKET Use After Free (packet_sock)

Vulnerability Summary
UAF vulnerability in Linux Kernel’s implementation of AF_PACKET leads to privilege escalation. AF_PACKET sockets allow users to send or receive packets on the device driver level, which lets them implement their own protocol on top of the physical layer or sniffing packets including Ethernet and higher levels protocol and higher levels of the OSI model.

CVE
CVE-2018-18559

Credit
An independent security researcher has reported this vulnerability to Beyond Security’s SecuriTeam Secure Disclosure program.

Affected systems
Ubuntu Desktop versions 14.04, 16.04, 17.10, and other Linux distributions with older kernel versions. The vulnerability has been resolved in the latest Linux Kernel version 4.17.11.
Continue reading SSD Advisory – Linux Kernel AF_PACKET Use After Free (packet_sock)

SSD Advisory – Infiniband Linux Driver UAF

Vulnerability Summary
A bug in the threads synchronization of Infiniband Driver can cause an Use After Free. A struct that is allocated and free’d by a thread, is accessible through a second thread. If the second thread is calling the function “idr_find” before the struct was free’d by the first thread, then he can still use the struct after it was free’d.

Vendor Response
“Infiniband: fix a possible use-after-free bug has been added to the 4.17-stable tree. Patches currently in stable-queue are queue-4.17/infiniband-fix-a-possible-use-after-free-bug.patch”

CVE
CVE-2018-14737

Credit
An independent security researcher has reported this vulnerability to Beyond Security’s SecuriTeam Secure Disclosure program.
Continue reading SSD Advisory – Infiniband Linux Driver UAF

SSD Advisory – LINE Corporation URI Handlers Remote Commands Execution

Vulnerabilities Summary
LINE for Windows provided by LINE Corporation specifies the path to read DLL when launching software. A user clicking on a specially crafted link, can use this vulnerability to cause the user to insecurely load an arbitrary DLL which can be used to cause arbitrary code execution.

Vendor Response
“We released version 5.8.0 of the modified version LINE PC version (Windows version) on May 31, 2018, and we have automatically updated for all users. The update will be applied automatically on the system side when using the product. Also, when installing the LINE PC version (Windows version) from now on please use the latest installer”.

CVE
CVE-2018-0609

Credit
An independent security researcher has reported this vulnerability to Beyond Security’s SecuriTeam Secure Disclosure program.
Continue reading SSD Advisory – LINE Corporation URI Handlers Remote Commands Execution