CVE-2022-49562

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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2025-02-26 07:01

Updated : 2025-10-22 19:10

NVD link : CVE-2022-49562

Mitre link : CVE-2022-49562

CVE.ORG link : CVE-2022-49562

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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