Use-after-free in Linux kernel - CVE-2021-47634

Vulnerability identifier: #VU104502

CSH Severity: Low

CVSS v4 BT: 5.9 [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-2021-47634

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the vol_attribute_show() function in drivers/mtd/ubi/vmt.c, within the dev_attribute_show(), ubi_attach_mtd_dev() and uif_close() functions in drivers/mtd/ubi/build.c. A local user can escalate privileges on the system.

Linux kernel
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise High Availability Extension 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Live Patching
Ubuntu
openEuler
kgraft-patch-4_12_14-122_250-default
linux (Ubuntu package)
linux-fips (Ubuntu package)
kernel-default-debugsource
kernel-default-devel-debuginfo
kernel-default-man
kernel-macros
kernel-devel
kernel-default-base-debuginfo
kernel-default
kernel-default-debuginfo
kernel-default-kgraft
kernel-default-kgraft-devel
kernel-default-base
kernel-syms
cluster-md-kmp-default-debuginfo
dlm-kmp-default
kernel-default-devel
ocfs2-kmp-default-debuginfo
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
kernel-source
dlm-kmp-default-debuginfo
ocfs2-kmp-default
gfs2-kmp-default
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-tools-debuginfo
kernel-tools
python3-perf-debuginfo
python3-perf
python2-perf-debuginfo
python2-perf
perf-debuginfo
perf
kernel-tools-devel

Install update from vendor's website.

Linux kernel - update to 4.14.276
kgraft-patch-4_12_14-122_250-default - update to 1-8.3.1
linux (Ubuntu package) - addressed in versions 4.4.0.276.282, 4.4.0-276.310, 4.4.0.276.310~14.04.1, 4.4.0-276.310~14.04.1, 4.4.0.1150.147, 4.4.0-1150.156, 4.4.0.1151.148, 4.4.0-1151.162, 4.4.0.1188.192, 4.4.0-1188.203
linux-fips (Ubuntu package) - addressed in versions 4.4.0.1120.121, 4.4.0-1120.127
kernel-default-debugsource - update to 4.12.14-122.250.1
kernel-default-devel-debuginfo - update to 4.12.14-122.250.1
kernel-default-man - update to 4.12.14-122.250.1
kernel-macros - update to 4.12.14-122.250.1
kernel-devel - update to 4.12.14-122.250.1
kernel-default-base-debuginfo - update to 4.12.14-122.250.1
kernel-default - update to 4.12.14-122.250.1
kernel-default-debuginfo - update to 4.12.14-122.250.1
kernel-default-kgraft - update to 4.12.14-122.250.1
kernel-default-kgraft-devel - update to 4.12.14-122.250.1
kernel-default-base - update to 4.12.14-122.250.1
kernel-syms - update to 4.12.14-122.250.1
cluster-md-kmp-default-debuginfo - update to 4.12.14-122.250.1
dlm-kmp-default - update to 4.12.14-122.250.1
kernel-default-devel - update to 4.12.14-122.250.1
ocfs2-kmp-default-debuginfo - update to 4.12.14-122.250.1
cluster-md-kmp-default - update to 4.12.14-122.250.1
gfs2-kmp-default-debuginfo - update to 4.12.14-122.250.1
kernel-source - update to 4.12.14-122.250.1
dlm-kmp-default-debuginfo - update to 4.12.14-122.250.1
ocfs2-kmp-default - update to 4.12.14-122.250.1
gfs2-kmp-default - update to 4.12.14-122.250.1
kernel-devel - update to 4.19.90-2503.4.0.0320
kernel - update to 4.19.90-2503.4.0.0320
bpftool - update to 4.19.90-2503.4.0.0320
bpftool-debuginfo - update to 4.19.90-2503.4.0.0320
kernel-debuginfo - update to 4.19.90-2503.4.0.0320
kernel-debugsource - update to 4.19.90-2503.4.0.0320
kernel-tools-debuginfo - update to 4.19.90-2503.4.0.0320
kernel-source - update to 4.19.90-2503.4.0.0320
kernel-tools - update to 4.19.90-2503.4.0.0320
python3-perf-debuginfo - update to 4.19.90-2503.4.0.0320
python3-perf - update to 4.19.90-2503.4.0.0320
python2-perf-debuginfo - update to 4.19.90-2503.4.0.0320
python2-perf - update to 4.19.90-2503.4.0.0320
perf-debuginfo - update to 4.19.90-2503.4.0.0320
perf - update to 4.19.90-2503.4.0.0320
kernel-tools-devel - update to 4.19.90-2503.4.0.0320

• https://git.kernel.org/stable/c/1a3f1cf87054833242fcd0218de0481cf855f888
• https://git.kernel.org/stable/c/3cbf0e392f173ba0ce425968c8374a6aa3e90f2e
• https://git.kernel.org/stable/c/432b057f8e847ae5a2306515606f8d2defaca178
• https://git.kernel.org/stable/c/5f9e9c223e48c264241d2f34d0bfc29e5fcb5c1b
• https://git.kernel.org/stable/c/a8ecee49259f8f78d91ddb329ab2be7e6fd01974
• https://git.kernel.org/stable/c/c32fe764191b8ae8b128588beb96e3718d9179d8
• https://git.kernel.org/stable/c/d727fd32cbd1abf3465f607021bc9c746f17b5a8
• https://git.kernel.org/stable/c/f149b1bd213820363731aa119e5011ca892a2aac
• https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.276

• Use-after-free in Linux kernel mtd ubi driver
• SUSE update for the Linux Kernel
• openEuler 20.03 LTS SP4 update for kernel
• Ubuntu update for linux-fips
• Ubuntu update for linux