CVE-2022-48991

High

In the Linux kernel, the following vulnerability has been resolved: mm/khugepaged: invoke MMU notifiers in shmem/file collapse paths Any codepath that zaps page table entries must invoke MMU notifiers to ensure that secondary MMUs (like KVM) don't keep accessing pages which aren't mapped anymore. Secondary MMUs don't hold their own references to pages that are mirrored over, so failing to notify them can lead to page use-after-free. I'm marking this as addressing an issue introduced in commit f3f0e1d2150b ("khugepaged: add support of collapse for tmpfs/shmem pages"), but most of the security impact of this only came in commit 27e1f8273113 ("khugepaged: enable collapse pmd for pte-mapped THP"), which actually omitted flushes for the removal of present PTEs, not just for the removal of empty page tables.

Package Linux Kernel
Published 2024-10-21
Last modified 2024-11-07
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

7.8

out of 10
High
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness type

CWE-416

CVE-2022-48991 is a Use After Free vulnerability

What is Use After Free?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE

Affected versions

Linux kernel versions 4.8 and later are affected. Fixed in 4.9.337, 4.14.303, 4.19.270, 5.4.227, 5.10.159, 5.15.83, 6.0.13, 6.1 and their respective stable series.

Affected from
≥ 4.8
Fixed in
✓ 4.9.337 4.9.x ✓ 4.14.303 4.14.x ✓ 4.19.270 4.19.x ✓ 5.4.227 5.4.x ✓ 5.10.159 5.10.x ✓ 5.15.83 5.15.x ✓ 6.0.13 6.0.x ✓ 6.1

References

The following references provide additional information about CVE-2022-48991 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2022-48991?

    CVE-2022-48991 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 4.8 onward and has been patched in 4.9.337, 4.14.303, 4.19.270 and others. CVE-2022-48991 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2022-48991?

    CVE-2022-48991 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H .

  • Is there a patch available for CVE-2022-48991?

    Yes — CVE-2022-48991 has been patched. Fixed versions include 4.9.337, 4.14.303, 4.19.270 and others. If you are running Linux kernel 4.8 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2022-48991 actively exploited?

    No — CVE-2022-48991 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Use After Free (CWE-416)?

    The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →