CVE-2022-49562
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
26/02/2025
Last modified:
22/10/2025
Description
In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
KVM: x86: Use __try_cmpxchg_user() to update guest PTE A/D bits<br />
<br />
Use the recently introduced __try_cmpxchg_user() to update guest PTE A/D<br />
bits instead of mapping the PTE into kernel address space. The VM_PFNMAP<br />
path is broken as it assumes that vm_pgoff is the base pfn of the mapped<br />
VMA range, which is conceptually wrong as vm_pgoff is the offset relative<br />
to the file and has nothing to do with the pfn. The horrific hack worked<br />
for the original use case (backing guest memory with /dev/mem), but leads<br />
to accessing "random" pfns for pretty much any other VM_PFNMAP case.
Impact
Base Score 3.x
5.50
Severity 3.x
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.2 (including) | 5.17.13 (excluding) |
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.18 (including) | 5.18.2 (excluding) |
To consult the complete list of CPE names with products and versions, see this page