Race condition in Linux kernel - CVE-2021-47461
Published: July 1, 2024 / Updated: May 13, 2025
Vulnerability identifier: #VU93603
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-47461
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition within the userfaultfd_writeprotect() function in fs/userfaultfd.c. A local user can escalate privileges on the system.
How to mitigate CVE-2021-47461
Install update from vendor's website.
Sources
- https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525
- https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a
- https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.76
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14.15
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15