CVE-2021-47461

Medium

In the Linux kernel, the following vulnerability has been resolved: userfaultfd: fix a race between writeprotect and exit_mmap() A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called. The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well. Use mmget_not_zero() to prevent the race as done in other userfaultfd operations.

Package Linux Kernel
Published 2024-05-22
Last modified 2025-09-24
CVSS version 3.1
Patch available
Awaiting data

CVSS 3.1 score

4.7

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

Weakness type

CWE-362

CVE-2021-47461 is a Race Condition vulnerability

What is Race Condition?

The product contains a code sequence that can run concurrently with other code, creating unexpected states. Learn more on MITRE CWE

References

The following references provide additional information about CVE-2021-47461 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-2021-47461?

    CVE-2021-47461 is a Medium severity Linux kernel vulnerability with a CVSS score of 4.7 out of 10 , classified as a Race Condition flaw (CWE-362) . CVE-2021-47461 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2021-47461?

    CVE-2021-47461 has a CVSS score of 4.7 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2021-47461?

    No patch is currently available for CVE-2021-47461. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

  • Is CVE-2021-47461 actively exploited?

    No — CVE-2021-47461 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Race Condition (CWE-362)?

    The product contains a code sequence that can run concurrently with other code, creating unexpected states. View CWE-362 on MITRE CWE →