CVE-2021-22543 (GCVE-0-2021-22543)

Vulnerability from cvelistv5 – Published: 2021-05-26 10:30 – Updated: 2024-09-16 23:26
VLAI
Title
Improper memory handling in Linux KVM
Summary
An issue was discovered in Linux: KVM through Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass RO checks and can lead to pages being freed while still accessible by the VMM and guest. This allows users with the ability to start and control a VM to read/write random pages of memory and can result in local privilege escalation.
Severity
8.7 (High)
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L
CWE
  • CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer
Assigner
References
Impacted products
Vendor Product Version
Linux Kernel Linux Kernel Affected: add6a0cd1c5ba51b201e1361b05a5df817083618 , < f8be156be163a052a067306417cd0ff679068c97 (git)
Create a notification for this product.
Date Public
2021-05-17 14:00
Credits
David Stevens Kevin Hamacher Jann Horn
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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