#VU104499 Use-after-free in Linux kernel - CVE-2021-47646
Published: February 26, 2025 / Updated: May 11, 2025
Vulnerability identifier: #VU104499
Vulnerability risk: Low
CVSSv4.0: 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-2021-47646
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error within the bfq_setup_merge() and bfq_setup_cooperator() functions in block/bfq-iosched.c. A local user can escalate privileges on the system.
Remediation
Install update from vendor's website.
External links
- https://git.kernel.org/stable/c/15729ff8143f8135b03988a100a19e66d7cb7ecd
- https://git.kernel.org/stable/c/4083925bd6dc89216d156474a8076feec904e607
- https://git.kernel.org/stable/c/65d8a737452e88f251fe5d925371de6d606df613
- https://git.kernel.org/stable/c/931aff627469a75c77b9fd3823146d0575afffd6
- https://git.kernel.org/stable/c/abc2129e646af7b43025d90a071f83043f1ae76c
- https://git.kernel.org/stable/c/cc051f497eac9d8a0d816cd4bffa3415f2724871
- https://git.kernel.org/stable/c/f990f0985eda59d4f29fc83fcf300c92b1225d39
- https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.238