Use-after-free in Linux kernel - CVE-2020-8428

Vulnerability identifier: #VU24834

CSH Severity: Low

CVSS v4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2020-8428

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: Public exploit is available

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error within the "may_create_in_sticky" in "fs/namei.c". A local user can cause a denial of service (OOPS) or possibly obtain sensitive information from kernel memory.

Linux kernel
Anolis OS
bpftool
kernel
kernel-debug
kernel-debug-devel
kernel-devel
kernel-headers
kernel-tools
kernel-tools-libs
kernel-tools-libs-devel
perf
python-perf

Install updates from vendor's website.

Linux kernel - update to 5.5
bpftool - update to 4.19.91-26
kernel - update to 4.19.91-26
kernel-debug - update to 4.19.91-26
kernel-debug-devel - update to 4.19.91-26
kernel-devel - update to 4.19.91-26
kernel-headers - update to 4.19.91-26
kernel-tools - update to 4.19.91-26
kernel-tools-libs - update to 4.19.91-26
kernel-tools-libs-devel - update to 4.19.91-26
perf - update to 4.19.91-26
python-perf - update to 4.19.91-26

• Exploit #5489 - CVE-2020-8428-demo (reproduce a kernel bug) (May 26, 2021)
• Exploit #5467 - CVE_EXPLOIT () (May 24, 2021)

• http://www.openwall.com/lists/oss-security/2020/01/28/4
• http://www.openwall.com/lists/oss-security/2020/02/02/1
• https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d0cb50185ae942b03c4327be322055d622dc79f6
• https://github.com/torvalds/linux/commit/d0cb50185ae942b03c4327be322055d622dc79f6
• https://www.openwall.com/lists/oss-security/2020/01/28/2

• Denial of service in Linux Kernel
• Anolis OS update for kernel(ANCK)4.19