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Fencer Vulns
medium 5.1

CVE-2020-36558 json

A race condition in the Linux kernel before 5.5.7 involving VT_RESIZEX could lead to a NULL pointer dereference and general protection faul…

published 2022-07-21 4 y ago modified 2026-10-08 31 d ago also EUVD-2020-24034

cvss
5.1
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits
0
none known

Summary

A race condition in the Linux kernel before 5.5.7 involving VT_RESIZEX could lead to a NULL pointer dereference and general protection fault.

Patch / fix

  • linux linux_kernel 5.5.7
  • linux Debian 14, Debian 13, Debian 12 5.5.13-1

debian advisories DEBIAN-CVE-2020-36558

  • linux Ubuntu 16.04 LTS 4.4.0-178.208
  • linux Ubuntu 18.04 LTS 4.15.0-99.100
  • linux-aws Ubuntu 16.04 LTS 4.4.0-1106.117
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1066.70
  • linux-gcp Ubuntu 16.04 LTS 4.15.0-1061.65
  • linux-hwe Ubuntu 16.04 LTS 4.15.0-99.100~16.04.1
  • linux-kvm Ubuntu 16.04 LTS 4.4.0-1070.77
  • linux-kvm Ubuntu 18.04 LTS 4.15.0-1059.60

ubuntu advisories UBUNTU-CVE-2020-36558

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • perf rhev hypervisor 4.4, RHEL 8.6 EUS 4.18.0-372.75.1.el8_6
  • kernel RHEL 8 4.18.0-425.3.1.el8
  • perf RHEL 8 4.18.0-425.3.1.el8
  • bpftool RHEL 8 4.18.0-425.3.1.el8
  • kernel-core RHEL 8 4.18.0-425.3.1.el8
  • kernel-tools RHEL 8 4.18.0-425.3.1.el8
  • python3-perf RHEL 8 4.18.0-425.3.1.el8
  • kernel-modules RHEL 8 4.18.0-425.3.1.el8

red hat advisories RHSA-2023:5627RHSA-2022:7683RHSA-2022:7444RHSA-2024:2003RHSA-2024:2004

  • kernel-syms SLES for SAP 12 SP4, SLES 12 SP4-LTSS, OpenStack Cloud Crowbar 9 +1 more 4.12.14-95.108.1
  • kernel-source SLES for SAP 12 SP4, SLES 12 SP4-LTSS, OpenStack Cloud Crowbar 9 +1 more 4.12.14-95.108.1
  • kernel-default SLES for SAP 12 SP4, SLES 12 SP4-LTSS, SLE Live Patching 12 SP4 +3 more 4.12.14-95.108.1
  • kernel-rt SLE Real Time 12 SP5 4.12.14-10.97.1
  • kernel-syms-rt SLE Real Time 12 SP5 4.12.14-10.97.1
  • kernel-rt_debug SLE Real Time 12 SP5 4.12.14-10.97.1
  • kernel-source-rt SLE Real Time 12 SP5 4.12.14-10.97.1
  • kernel-rt SLE Micro 5.2, SLE Micro 5.1, Real Time Module 15 SP3 +1 more 5.3.18-150300.99.1

suse advisories SUSE-SU-2023:0416-1SUSE-SU-2022:4129-1SUSE-SU-2022:4027-1SUSE-SU-2022:3274-1SUSE-SU-2022:2910-1SUSE-SU-2022:2892-2

  • kernel-rt AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-kvm AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-core AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-modules AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-debug-kvm AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-debug-core AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-debug-modules AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8
  • kernel-rt-modules-extra AlmaLinux 8 4.18.0-425.3.1.rt7.213.el8

almalinux advisories ALSA-2022:7444ALSA-2022:7683

  • kernel Rocky Linux 8 4.18.0-425.3.1.el8
  • kernel-rt Rocky Linux 8 4.18.0-425.3.1.rt7.213.el8

rocky linux advisories RLSA-2022:7683RLSA-2022:7444

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-36558 updated cvss 5.1

kernel: race condition in VT_RESIZEX ioctl when vc_cons[i].d is already NULL leading to NULL pointer dereference

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: no fix available
  • Red Hat CodeReady Linux Builder (v. 8) kernel-debuginfo-common-x86_64 4.18.0-425.3.1.el8, kernel-debuginfo-common-aarch64 4.18.0-425.3.1.el8, kernel-debuginfo-common-ppc64le 4.18.0-425.3.1.el8
    fixed: vendor fix RHSA-2022:7683
  • Red Hat CodeReady Linux Builder EUS (v.8.6) kernel-debuginfo-common-x86_64 4.18.0-372.75.1.el8_6, kernel-debuginfo-common-aarch64 4.18.0-372.75.1.el8_6, kernel-debuginfo-common-ppc64le 4.18.0-372.75.1.el8_6
    fixed: vendor fix RHSA-2023:5627
  • Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-425.3.1.el8, kernel 4.18.0-425.3.1.el8, bpftool 4.18.0-425.3.1.el8, kernel-core 4.18.0-425.3.1.el8, kernel-tools 4.18.0-425.3.1.el8, python3-perf 4.18.0-425.3.1.el8, +15 more
    fixed: vendor fix RHSA-2022:7683
  • Red Hat Enterprise Linux BaseOS EUS (v.8.6) perf 4.18.0-372.75.1.el8_6, kernel 4.18.0-372.75.1.el8_6, bpftool 4.18.0-372.75.1.el8_6, kernel-core 4.18.0-372.75.1.el8_6, kernel-tools 4.18.0-372.75.1.el8_6, python3-perf 4.18.0-372.75.1.el8_6, +15 more
    fixed: vendor fix RHSA-2023:5627
  • Red Hat Enterprise Linux Client (v. 7) perf 3.10.0-1160.118.1.el7, kernel 3.10.0-1160.118.1.el7, bpftool 3.10.0-1160.118.1.el7, python-perf 3.10.0-1160.118.1.el7, kernel-tools 3.10.0-1160.118.1.el7, kernel-tools-libs 3.10.0-1160.118.1.el7, +2 more Red Hat Enterprise Linux Client Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.118.1.el7 Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.118.1.el7
    fixed: vendor fix RHSA-2024:2004
  • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-trace 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1160.118.1.rt56.1269.el7 Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-kvm 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-trace 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-debug-kvm 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-trace-kvm 3.10.0-1160.118.1.rt56.1269.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1160.118.1.rt56.1269.el7
    fixed: vendor fix RHSA-2024:2003
  • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt 4.18.0-425.3.1.rt7.213.el8, kernel-rt-core 4.18.0-425.3.1.rt7.213.el8, kernel-rt-modules 4.18.0-425.3.1.rt7.213.el8, kernel-rt-debug-core 4.18.0-425.3.1.rt7.213.el8, kernel-rt-debug-modules 4.18.0-425.3.1.rt7.213.el8, kernel-rt-modules-extra 4.18.0-425.3.1.rt7.213.el8, +2 more Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt 4.18.0-425.3.1.rt7.213.el8, kernel-rt-kvm 4.18.0-425.3.1.rt7.213.el8, kernel-rt-core 4.18.0-425.3.1.rt7.213.el8, kernel-rt-modules 4.18.0-425.3.1.rt7.213.el8, kernel-rt-debug-kvm 4.18.0-425.3.1.rt7.213.el8, kernel-rt-debug-core 4.18.0-425.3.1.rt7.213.el8, +4 more
    fixed: vendor fix RHSA-2022:7444
show 3 more
  • Red Hat Enterprise Linux Server (v. 7) perf 3.10.0-1160.118.1.el7, kernel 3.10.0-1160.118.1.el7, bpftool 3.10.0-1160.118.1.el7, python-perf 3.10.0-1160.118.1.el7, kernel-kdump 3.10.0-1160.118.1.el7, kernel-tools 3.10.0-1160.118.1.el7, +7 more Red Hat Enterprise Linux Server Optional (v. 7) kernel-debuginfo-common-ppc64 3.10.0-1160.118.1.el7, kernel-debuginfo-common-x86_64 3.10.0-1160.118.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-1160.118.1.el7 Red Hat Enterprise Linux Workstation (v. 7) perf 3.10.0-1160.118.1.el7, kernel 3.10.0-1160.118.1.el7, bpftool 3.10.0-1160.118.1.el7, python-perf 3.10.0-1160.118.1.el7, kernel-tools 3.10.0-1160.118.1.el7, kernel-tools-libs 3.10.0-1160.118.1.el7, +2 more Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1160.118.1.el7
    fixed: vendor fix RHSA-2024:2004
  • Red Hat Virtualization 4 Hypervisor for RHEL 8 perf 4.18.0-372.75.1.el8_6, kernel-debuginfo-common-x86_64 4.18.0-372.75.1.el8_6
    fixed: vendor fix RHSA-2023:5627
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
31 d ago

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • git.kernel.org https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6cd1ed50efd88261298577cd92a14f2768eddeeb referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 5.1 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Classification

Weakness
  • CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization
  • CWE-476 NULL Pointer Dereference
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.