PT-2024-11340 · Linux+2 · Linux Kernel+2

Published

2021-07-14

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Updated

2025-01-14

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CVE-2021-47341

CVSS v3.1

7.8

High

VectorAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Name of the Vulnerable Software and Affected Versions Linux kernel version 5.10.0
Description A use-after-free vulnerability has been identified in the Linux kernel, specifically in the KVM (Kernel-based Virtual Machine) module. The vulnerability occurs when the kvm vm ioctl unregister coalesced mmio function is called, which can lead to a read operation on a freed memory region. This issue is detected by the KASAN (Kernel Address Sanitizer) tool.
The vulnerability is caused by a bug in the kvm vm ioctl unregister coalesced mmio function, which fails to properly handle the memory region after it has been freed. This can result in a use-after-free error, potentially allowing an attacker to exploit the vulnerability.
The estimated number of potentially affected devices worldwide is not available. There is no information about real-world incidents where this issue was exploited.
Technical details about exploitation include:
  • The kvm vm ioctl unregister coalesced mmio function is vulnerable to a use-after-free error.
  • The kasan report function is called to report the use-after-free error.
  • The asan load8 function is used to detect the use-after-free error.
Recommendations To resolve this issue, update the Linux kernel to a version that includes the fix for the kvm vm ioctl unregister coalesced mmio function. As a temporary workaround, consider disabling the KVM module or restricting access to the vulnerable function until a patch is available.

Fix

Use After Free

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Weakness Enumeration

Related Identifiers

BDU:2025-07330
CVE-2021-47341
OPENSUSE-SU-2024_2185-1
SUSE-SU-2024:2010-1
SUSE-SU-2024:2183-1
SUSE-SU-2024:2185-1
SUSE-SU-2024:3189-1
SUSE-SU-2024:3251-1
SUSE-SU-2024:3252-1

Affected Products

Astra Linux
Linux Kernel
Suse