Linux Kernel modify_ldt() Memory Protection Extensions Bounds Violation Use-After-Free Vulnerability [CVE-2019-13233]

CVE Number – CVE-2019-13233

A vulnerability in the Linux Kernel could allow a local attacker to execute arbitrary code on a targeted system.The vulnerability is due to a race condition between the modify_ldt() function and a #BR exception for an Memory Protection Extensions (MPX) bounds violation in the affected software. An attacker could exploit this vulnerability by accessing the system and executing an application that submits malicious input to the system. A successful exploit could cause a race condition that leads to a use-after-free memory operation error, which could allow the attacker to execute arbitrary code on the targeted system.kernel.org has confirmed the vulnerability and released software updates.

Analysis

• To exploit this vulnerability, the attacker must have user-level access to the system. This access requirement could reduce the likelihood of a successful exploit.

Safeguards

• Administrators are advised to apply the appropriate updates.
  
  Administrators are advised to allow only trusted users to access local systems.
  
  Administrators are advised to allow only privileged users to access administration or management systems.
  
  Administrators are advised to monitor critical systems.

Vendor Announcements

• kernel.org has released a Changelog at the following link: ChangeLog 5.1.9

Fixed Software

• kernel.org has released a software patch at the following link: x86/insn-eval: Fix use-after-free access to LDT entry