CVE-2021-28964
kernel: race condition in get_old_root function in fs/btrfs/ctree.c because of a lack of locking on an extent buffer before a cloning operation
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · March 16, 2021
Updated · June 28, 2026
Description
A race condition flaw was found in get_old_root in fs/btrfs/ctree.c in the Linux kernel in btrfs file-system. This flaw allows a local attacker with a special user privilege to cause a denial of service due to not locking an extent buffer before a cloning operation. The highest threat from this vulnerability is to system availability.
Statement
This issue affected Linux kernel versions as shipped with Red Hat Enterprise Linux 7 / 7-RT.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 4.1CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
CWE-413 · Improper Resource Locking