Use after free in Linux kernel - CVE-2020-14381

Vulnerability identifier: #VU92420

CSH Severity: Low

CVSS v4: 8.5 [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]

CVE-ID: CVE-2020-14381

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to execute arbitrary code.

The vulnerability exists due to use after free error within the get_futex_key_refs(), drop_futex_key_refs() and futex_setup_timer() functions in kernel/futex.c, within the inode_init_always() function in fs/inode.c. A local user can execute arbitrary code.

Linux kernel
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
kernel (Red Hat package)

Install update from vendor's repository.

kernel (Red Hat package) - update to 4.18.0-240.el8

• https://bugzilla.redhat.com/show_bug.cgi?id=1874311
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=8019ad13ef7f64be44d4f892af9c840179009254

• Use after free in Linux kernel fs
• Red Hat Enterprise Linux 8 update for kernel