Use After Free Affecting kernel-rt-debug-kvm package, versions *


Severity

Recommended
low

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.04% (15th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Use After Free vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-RHEL9-KERNELRTDEBUGKVM-6969974
  • published22 May 2024
  • disclosed21 May 2024

Introduced: 21 May 2024

CVE-2021-47334  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:9 kernel-rt-debug-kvm.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-rt-debug-kvm package and not the kernel-rt-debug-kvm package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

misc/libmasm/module: Fix two use after free in ibmasm_init_one

In ibmasm_init_one, it calls ibmasm_init_remote_input_dev(). Inside ibmasm_init_remote_input_dev, mouse_dev and keybd_dev are allocated by input_allocate_device(), and assigned to sp->remote.mouse_dev and sp->remote.keybd_dev respectively.

In the err_free_devices error branch of ibmasm_init_one, mouse_dev and keybd_dev are freed by input_free_device(), and return error. Then the execution runs into error_send_message error branch of ibmasm_init_one, where ibmasm_free_remote_input_dev(sp) is called to unregister the freed sp->remote.mouse_dev and sp->remote.keybd_dev.

My patch add a "error_init_remote" label to handle the error of ibmasm_init_remote_input_dev(), to avoid the uaf bugs.

CVSS Scores

version 3.1