CVE-2022-49562

MEDIUM EPSS 14.6%
Published Feb 26, 20251y ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Feb 26, 2025 1y ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Use __try_cmpxchg_user() to update guest PTE A/D bits Use the recently introduced __try_cmpxchg_user() to update guest PTE A/D bits instead of mapping the PTE into kernel address space. The VM_PFNMAP path is broken as it assumes that vm_pgoff is the base pfn of the mapped VMA range, which is conceptually wrong as vm_pgoff is the offset relative to the file and has nothing to do with the pfn. The horrific hack worked for the original use case (backing guest memory with /dev/mem), but leads to accessing "random" pfns for pretty much any other VM_PFNMAP case.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
14.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 2

VendorProductVersionRange
linuxlinux_kernel*≥5.2  –  <5.17.13
linuxlinux_kernel*≥5.18  –  <5.18.2

References 3

  • git.kernel.org https://git.kernel.org/stable/c/38b888911e8dc89b89d8147cfb1d2dbe6373bf78
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8089e5e1d18402fb8152d6b6815450a36fffa9b0
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f122dfe4476890d60b8c679128cd2259ec96a24c
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/38b888911e8dc89b89d8147cfb1d2dbe6373bf78
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8089e5e1d18402fb8152d6b6815450a36fffa9b0
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/f122dfe4476890d60b8c679128cd2259ec96a24c
    Patch