Use-after-free in Linux kernel - CVE-2020-36694

Vulnerability identifier: #VU77254

CSH Severity: Low

CVSS v4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2020-36694

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 in the packet processing context, because the per-CPU sequence count is mishandled during concurrent iptables rules replacement. A local user with CAP_NET_ADMIN capability in an unprivileged namespace can execute arbitrary code with elevated privileges.

Linux kernel
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Manager Proxy
SUSE Manager Retail Branch Server
SUSE Manager Server
SUSE Linux Enterprise Micro
SUSE Linux Enterprise Micro for Rancher
SUSE Enterprise Storage
SUSE Linux Enterprise High Performance Computing 15 SP2 LTSS
SUSE Linux Enterprise Live Patching
SUSE Linux Enterprise Server 15 SP2 Business Critical Linux
SUSE Linux Enterprise Server 15 SP2 LTSS
SUSE Linux Enterprise Server 15 SP3 LTSS
SUSE Linux Enterprise Server 15 SP3 Business Critical Linux
SUSE Real Time Module
openSUSE Leap
openEuler
kernel-livepatch-5_3_18-150200_24_154-default
kernel-livepatch-5_3_18-150200_24_154-default-debuginfo
kernel-livepatch-SLE15-SP2_Update_37-debugsource
kernel-livepatch-5_3_18-150300_59_124-default
python2-perf-debuginfo
kernel
bpftool-debuginfo
python2-perf
kernel-devel
kernel-debuginfo
kernel-source
python3-perf
python3-perf-debuginfo
kernel-tools
perf-debuginfo
bpftool
kernel-debugsource
kernel-tools-debuginfo
kernel-tools-devel
perf
kernel-preempt-devel-debuginfo
kernel-preempt-debugsource
kernel-obs-build
kernel-preempt
kernel-default
kernel-default-debugsource
kernel-default-devel-debuginfo
dlm-kmp-default
ocfs2-kmp-default-debuginfo
kernel-default-debuginfo
gfs2-kmp-default-debuginfo
dlm-kmp-default-debuginfo
cluster-md-kmp-default-debuginfo
ocfs2-kmp-default
gfs2-kmp-default
cluster-md-kmp-default
kernel-obs-build-debugsource
kernel-default-devel
kernel-preempt-devel
kernel-preempt-debuginfo
kernel-default-livepatch
kernel-macros
kernel-syms
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-default-livepatch-devel
kernel-default-base
kernel-docs
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-zfcpdump
kernel-64kb
dtb-al
dtb-zte
dtb-aarch64
kernel-64kb-devel
kernel-64kb-debuginfo
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
dlm-kmp-rt
ocfs2-kmp-rt
kernel-rt-debuginfo
dlm-kmp-rt-debuginfo
kernel-rt-debugsource
cluster-md-kmp-rt-debuginfo
gfs2-kmp-rt
cluster-md-kmp-rt
kernel-rt_debug-devel
kernel-rt_debug-devel-debuginfo
ocfs2-kmp-rt-debuginfo
kernel-rt_debug-debuginfo
kernel-rt_debug-debugsource
kernel-rt-devel-debuginfo
gfs2-kmp-rt-debuginfo
kernel-syms-rt
kernel-devel-rt
kernel-source-rt
kernel-rt
kernel-rt_debug
kernel-rt-devel
EMC Cloud Tiering Appliance

Install updates from vendor's website.

Linux kernel - addressed in versions 5.10, 5.12
kernel-livepatch-5_3_18-150200_24_154-default - update to 1-150200.5.3.1
kernel-livepatch-5_3_18-150200_24_154-default-debuginfo - update to 1-150200.5.3.1
kernel-livepatch-SLE15-SP2_Update_37-debugsource - update to 1-150200.5.3.1
kernel-livepatch-5_3_18-150300_59_124-default - update to 1-150300.7.3.1
python2-perf-debuginfo - update to 4.19.90-2305.4.0.0203
kernel - update to 4.19.90-2305.4.0.0203
bpftool-debuginfo - update to 4.19.90-2305.4.0.0203
python2-perf - update to 4.19.90-2305.4.0.0203
kernel-devel - update to 4.19.90-2305.4.0.0203
kernel-debuginfo - update to 4.19.90-2305.4.0.0203
kernel-source - update to 4.19.90-2305.4.0.0203
python3-perf - update to 4.19.90-2305.4.0.0203
python3-perf-debuginfo - update to 4.19.90-2305.4.0.0203
kernel-tools - update to 4.19.90-2305.4.0.0203
perf-debuginfo - update to 4.19.90-2305.4.0.0203
bpftool - update to 4.19.90-2305.4.0.0203
kernel-debugsource - update to 4.19.90-2305.4.0.0203
kernel-tools-debuginfo - update to 4.19.90-2305.4.0.0203
kernel-tools-devel - update to 4.19.90-2305.4.0.0203
perf - update to 4.19.90-2305.4.0.0203
kernel-preempt-devel-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-preempt-debugsource - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-obs-build - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-preempt - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-debugsource - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-devel-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
dlm-kmp-default - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
ocfs2-kmp-default-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
gfs2-kmp-default-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
dlm-kmp-default-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
cluster-md-kmp-default-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
ocfs2-kmp-default - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
gfs2-kmp-default - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
cluster-md-kmp-default - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-obs-build-debugsource - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-devel - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-preempt-devel - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-preempt-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-livepatch - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-macros - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-source - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-devel - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-syms - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
reiserfs-kmp-default - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
reiserfs-kmp-default-debuginfo - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-livepatch-devel - addressed in versions 5.3.18-150200.24.154.1, 5.3.18-150300.59.124.1
kernel-default-base - addressed in versions 5.3.18-150200.24.154.1.150200.9.75.1, 5.3.18-150300.59.124.1.150300.18.72.1
kernel-docs - addressed in versions 5.3.18-150200.24.154.2, 5.3.18-150300.59.124.1
kernel-zfcpdump-debugsource - update to 5.3.18-150300.59.124.1
kernel-zfcpdump-debuginfo - update to 5.3.18-150300.59.124.1
kernel-zfcpdump - update to 5.3.18-150300.59.124.1
kernel-64kb - update to 5.3.18-150300.59.124.1
dtb-al - update to 5.3.18-150300.59.124.1
dtb-zte - update to 5.3.18-150300.59.124.1
dtb-aarch64 - update to 5.3.18-150300.59.124.1
kernel-64kb-devel - update to 5.3.18-150300.59.124.1
kernel-64kb-debuginfo - update to 5.3.18-150300.59.124.1
kernel-64kb-debugsource - update to 5.3.18-150300.59.124.1
kernel-64kb-devel-debuginfo - update to 5.3.18-150300.59.124.1
dlm-kmp-rt - update to 5.3.18-150300.130.1
ocfs2-kmp-rt - update to 5.3.18-150300.130.1
kernel-rt-debuginfo - update to 5.3.18-150300.130.1
dlm-kmp-rt-debuginfo - update to 5.3.18-150300.130.1
kernel-rt-debugsource - update to 5.3.18-150300.130.1
cluster-md-kmp-rt-debuginfo - update to 5.3.18-150300.130.1
gfs2-kmp-rt - update to 5.3.18-150300.130.1
cluster-md-kmp-rt - update to 5.3.18-150300.130.1
kernel-rt_debug-devel - update to 5.3.18-150300.130.1
kernel-rt_debug-devel-debuginfo - update to 5.3.18-150300.130.1
ocfs2-kmp-rt-debuginfo - update to 5.3.18-150300.130.1
kernel-rt_debug-debuginfo - update to 5.3.18-150300.130.1
kernel-rt_debug-debugsource - update to 5.3.18-150300.130.1
kernel-rt-devel-debuginfo - update to 5.3.18-150300.130.1
gfs2-kmp-rt-debuginfo - update to 5.3.18-150300.130.1
kernel-syms-rt - update to 5.3.18-150300.130.1
kernel-devel-rt - update to 5.3.18-150300.130.1
kernel-source-rt - update to 5.3.18-150300.130.1
kernel-rt - update to 5.3.18-150300.130.1
kernel-rt_debug - update to 5.3.18-150300.130.1
kernel-rt-devel - update to 5.3.18-150300.130.1
EMC Cloud Tiering Appliance - update to 13.2.0.2.24

• https://syzkaller.appspot.com/bug?id=0c4fd9c6aa04ec116d01e915d3b186f71a212cb2
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cc00bcaa589914096edef7fb87ca5cee4a166b5c
• https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12
• https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10

• Privilege escalation in Linux kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• Multiple vulnerabilities in Dell Cloud Tiering Appliance
• openEuler 20.03 LTS SP1 update for kernel