Permissions, Privileges, and Access Controls in Util-linux - CVE-2021-3996

Vulnerability identifier: #VU60005

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2021-3996

CWE-ID: CWE-264

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to bypass implemented security restrictions.

The vulnerability exists due to improper UID check in libmount. A local user can unmount FUSE filesystems of users with similar UID.

Util-linux
util-linux (Debian package)
libeconf-debugsource
libeconf0
libeconf0-debuginfo
mount (Ubuntu package)
util-linux (Ubuntu package)
python-libmount
libuuid
libmount
util-linux-devel
util-linux-debuginfo
uuidd
util-linux-debugsource
libsmartcols
util-linux-user
libfdisk
util-linux-help
libblkid
util-linux
util-linux-systemd-debugsource
util-linux-systemd-debuginfo
util-linux-systemd
uuidd-debuginfo
libblkid1-debuginfo
libuuid1-32bit
libfdisk1
libfdisk1-debuginfo
libmount1
libmount1-debuginfo
libsmartcols1
libsmartcols1-debuginfo
libuuid1
libuuid1-debuginfo
libmount-devel
libuuid-devel-static
libuuid-devel
libsmartcols-devel
util-linux-lang
libfdisk-devel
libblkid1
libblkid-devel-static
libblkid-devel
libuuid1-32bit-debuginfo
libmount1-32bit-debuginfo
libmount1-32bit
libblkid1-32bit-debuginfo
libblkid1-32bit
shadow-debugsource
shadow
shadow-debuginfo
login_defs
SUSE Manager Server
SUSE Manager Proxy
SUSE Linux Enterprise Micro
SUSE Linux Enterprise Module for Server Applications
SUSE Linux Enterprise Server for SAP Applications
SUSE Linux Enterprise Module for Transactional Server
SUSE Linux Enterprise Module for Basesystem
SUSE Linux Enterprise Desktop
SUSE Linux Enterprise Server
SUSE Linux Enterprise High Performance Computing
openEuler
Ubuntu
Fedora

Install updates from vendor's website.

Util-linux - update to 2.37.3
util-linux (Debian package) - update to 2.36.1-8+deb11u1
libeconf-debugsource - update to 0.4.4+git20220104.962774f-150300.3.6.2
libeconf0 - update to 0.4.4+git20220104.962774f-150300.3.6.2
libeconf0-debuginfo - update to 0.4.4+git20220104.962774f-150300.3.6.2
mount (Ubuntu package) - addressed in versions 2.34-0.1ubuntu9.3, 2.36.1-8ubuntu2.2
util-linux (Ubuntu package) - addressed in versions 2.34-0.1ubuntu9.3, 2.36.1-8ubuntu2.2
python-libmount - update to 2.35.2-10
libuuid - update to 2.35.2-10
libmount - update to 2.35.2-10
util-linux-devel - update to 2.35.2-10
util-linux-debuginfo - update to 2.35.2-10
uuidd - update to 2.35.2-10
util-linux-debugsource - update to 2.35.2-10
libsmartcols - update to 2.35.2-10
util-linux-user - update to 2.35.2-10
libfdisk - update to 2.35.2-10
util-linux-help - update to 2.35.2-10
libblkid - update to 2.35.2-10
util-linux - update to 2.35.2-10
uuidd - update to 2.36.2-150300.4.14.2
util-linux-systemd-debugsource - update to 2.36.2-150300.4.14.2
util-linux-systemd-debuginfo - update to 2.36.2-150300.4.14.2
util-linux-systemd - update to 2.36.2-150300.4.14.2
uuidd-debuginfo - update to 2.36.2-150300.4.14.2
libblkid1-debuginfo - update to 2.36.2-150300.4.14.3
libuuid1-32bit - update to 2.36.2-150300.4.14.3
libfdisk1 - update to 2.36.2-150300.4.14.3
libfdisk1-debuginfo - update to 2.36.2-150300.4.14.3
libmount1 - update to 2.36.2-150300.4.14.3
libmount1-debuginfo - update to 2.36.2-150300.4.14.3
libsmartcols1 - update to 2.36.2-150300.4.14.3
libsmartcols1-debuginfo - update to 2.36.2-150300.4.14.3
libuuid1 - update to 2.36.2-150300.4.14.3
libuuid1-debuginfo - update to 2.36.2-150300.4.14.3
util-linux - update to 2.36.2-150300.4.14.3
util-linux-debuginfo - update to 2.36.2-150300.4.14.3
util-linux-debugsource - update to 2.36.2-150300.4.14.3
libmount-devel - update to 2.36.2-150300.4.14.3
libuuid-devel-static - update to 2.36.2-150300.4.14.3
libuuid-devel - update to 2.36.2-150300.4.14.3
libsmartcols-devel - update to 2.36.2-150300.4.14.3
util-linux-lang - update to 2.36.2-150300.4.14.3
libfdisk-devel - update to 2.36.2-150300.4.14.3
libblkid1 - update to 2.36.2-150300.4.14.3
libblkid-devel-static - update to 2.36.2-150300.4.14.3
libblkid-devel - update to 2.36.2-150300.4.14.3
libuuid1-32bit-debuginfo - update to 2.36.2-150300.4.14.3
libmount1-32bit-debuginfo - update to 2.36.2-150300.4.14.3
libmount1-32bit - update to 2.36.2-150300.4.14.3
libblkid1-32bit-debuginfo - update to 2.36.2-150300.4.14.3
libblkid1-32bit - update to 2.36.2-150300.4.14.3
util-linux - update to 2.37.3-1.fc35
shadow-debugsource - update to 4.8.1-150300.4.3.8
shadow - update to 4.8.1-150300.4.3.8
shadow-debuginfo - update to 4.8.1-150300.4.3.8
login_defs - update to 4.8.1-150300.4.3.8

• https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
• https://www.openwall.com/lists/oss-security/2022/01/24/2

• Multiple vulnerabilities in Util-linux libmount
• Debian update for util-linux
• Ubuntu update for util-linux
• SUSE update for libeconf, shadow and util-linux
• SUSE update for libeconf, shadow and util-linux
• openEuler update for util-linux
• Fedora 35 update for util-linux