CVE-2021-47461

high

Published 2024-08-08 · Modified 2024-08-08

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CVSS v3

—

CVSS v4 NEW

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not yet in upstream

VIR risk

8.0

Description

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.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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OS impact

SUSE Affected 1 release

Version	Status	Fixed in
—	Affected	—

AlmaLinux Fixed 1 release

Version	Status	Fixed in
8	Fixed	`kernel-rt-debug-4.18.0-553.16.1.rt7.357.el8_10.x86_64.rpm`

Debian Fixed 5 releases

Version	Status	Fixed in
trixie	Fixed	`5.14.16-1`
sid	Fixed	`5.14.16-1`
forky	Fixed	`5.14.16-1`
bullseye	Fixed	`5.10.84-1`
bookworm	Fixed	`5.14.16-1`

Red Hat Fixed 1 release

Version	Status	Fixed in
8	Fixed	—

Rocky Linux Fixed 1 release

Version	Status	Fixed in
8	Fixed	—

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.