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Fencer Vulns
high 7.5

CVE-2019-14821 json

An out-of-bounds access issue was found in the Linux kernel, all versions through 5.3, in the way Linux kernel's KVM hypervisor implements…

published 2019-09-19 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-5949

cvss
7.5
version 3.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 55%
public exploits
0
none known

Summary

An out-of-bounds access issue was found in the Linux kernel, all versions through 5.3, in the way Linux kernel's KVM hypervisor implements the Coalesced MMIO write operation. It operates on an MMIO ring buffer 'struct kvm_coalesced_mmio' object, wherein write indices 'ring->first' and 'ring->last' value could be supplied by a host user-space process. An unprivileged host user or process with access to '/dev/kvm' device could use this flaw to crash the host kernel, resulting in a denial of service or potentially escalating privileges on the system.

Patch / fix

  • linux linux_kernel 3.16.74, 4.4.194, 4.9.194, 4.14.146, 4.19.75, 5.2.17, 5.3.1
  • linux Debian 14, Debian 13, Debian 12 5.2.17-1

debian advisories DEBIAN-CVE-2019-14821

  • linux Ubuntu 16.04 LTS 4.4.0-166.195
  • linux Ubuntu 18.04 LTS 4.15.0-66.75
  • linux-aws Ubuntu 16.04 LTS 4.4.0-1096.107
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1052.54
  • linux-gcp Ubuntu 16.04 LTS 4.15.0-1047.50
  • linux-gcp Ubuntu 18.04 LTS 5.0.0-1021.21~18.04.1
  • linux-hwe Ubuntu 16.04 LTS 4.15.0-66.75~16.04.1
  • linux-hwe Ubuntu 18.04 LTS 5.0.0-32.34~18.04.2

ubuntu advisories UBUNTU-CVE-2019-14821

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

  • kernel RHEL 8 4.18.0-147.el8
  • perf RHEL 8 4.18.0-147.el8
  • bpftool RHEL 8 4.18.0-147.el8
  • kernel-core RHEL 8 4.18.0-147.el8
  • kernel-tools RHEL 8 4.18.0-147.el8
  • python3-perf RHEL 8 4.18.0-147.el8
  • kernel-modules RHEL 8 4.18.0-147.el8
  • kernel-zfcpdump RHEL 8 4.18.0-147.el8

red hat advisories RHSA-2019:3517RHSA-2020:2851RHSA-2019:3309RHSA-2020:0204RHSA-2019:4154RHSA-2019:3979

  • kernel-azure SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-16.7.1
  • kernel-syms-azure SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-16.7.1
  • kernel-source-azure SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-16.7.1
  • kernel-rt Real Time Module 15 SP1 4.12.14-14.14.3
  • kernel-syms-rt Real Time Module 15 SP1 4.12.14-14.14.2
  • kernel-rt_debug Real Time Module 15 SP1 4.12.14-14.14.3
  • kernel-source-rt Real Time Module 15 SP1 4.12.14-14.14.2
  • kernel-syms SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-122.7.1

suse advisories SUSE-SU-2020:0093-1SUSE-SU-2019:3295-1SUSE-SU-2019:3200-1SUSE-SU-2019:2984-1SUSE-SU-2019:2949-1SUSE-SU-2019:14218-1

  • kernel-syms openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-obs-qa openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-source openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-default openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-vanilla openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-kvmsmall openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-obs-build openSUSE Leap 15.1 4.12.14-lp151.28.20.1
  • kernel-syms openSUSE Leap 15.0 4.12.14-lp150.12.76.1

opensuse advisories openSUSE-SU-2019:2308-1openSUSE-SU-2019:2307-1

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-2019-14821 updated cvss 7.0

Kernel: KVM: OOB memory access via mmio ring buffer

  • Red Hat Enterprise Linux 5 kernel
    affected: workaround, no fix planned “Restrict access to the '/dev/kvm' device to trusted users.”
  • Red Hat Enterprise Linux 7 perf, kernel, kernel-alt, python-perf, kernel-kdump, kernel-tools, +3 more
    affected: workaround, no fix available “Restrict access to the '/dev/kvm' device to trusted users.”
  • Red Hat CodeReady Linux Builder (v. 8) kernel-debuginfo-common-x86_64 4.18.0-147.el8, kernel-debuginfo-common-aarch64 4.18.0-147.el8, kernel-debuginfo-common-ppc64le 4.18.0-147.el8 Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-147.el8, kernel 4.18.0-147.el8, bpftool 4.18.0-147.el8, kernel-core 4.18.0-147.el8, kernel-tools 4.18.0-147.el8, python3-perf 4.18.0-147.el8, +15 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3517
  • Red Hat Enterprise Linux BaseOS E4S (v. 8.0) perf 4.18.0-80.15.1.el8_0, kernel 4.18.0-80.15.1.el8_0, bpftool 4.18.0-80.15.1.el8_0, kernel-core 4.18.0-80.15.1.el8_0, kernel-tools 4.18.0-80.15.1.el8_0, python3-perf 4.18.0-80.15.1.el8_0, +9 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2020:0204
  • Red Hat Enterprise Linux Client (v. 7) perf 3.10.0-1062.7.1.el7, kernel 3.10.0-1062.7.1.el7, bpftool 3.10.0-1062.7.1.el7, python-perf 3.10.0-1062.7.1.el7, kernel-tools 3.10.0-1062.7.1.el7, kernel-tools-libs 3.10.0-1062.7.1.el7, +2 more Red Hat Enterprise Linux Client Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1062.7.1.el7 Red Hat Enterprise Linux ComputeNode (v. 7) perf 3.10.0-1062.7.1.el7, kernel 3.10.0-1062.7.1.el7, bpftool 3.10.0-1062.7.1.el7, python-perf 3.10.0-1062.7.1.el7, kernel-tools 3.10.0-1062.7.1.el7, kernel-tools-libs 3.10.0-1062.7.1.el7, +2 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3979
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) perf 3.10.0-957.56.1.el7, kernel 3.10.0-957.56.1.el7, bpftool 3.10.0-957.56.1.el7, python-perf 3.10.0-957.56.1.el7, kernel-tools 3.10.0-957.56.1.el7, kernel-tools-libs 3.10.0-957.56.1.el7, +2 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2020:2851
  • Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1062.7.1.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3979
  • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) kernel-debuginfo-common-x86_64 3.10.0-957.56.1.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2020:2851
show 18 more
  • Red Hat Enterprise Linux Desktop (v. 6) perf 2.6.32-754.25.1.el6, kernel 2.6.32-754.25.1.el6, kernel-firmware 2.6.32-754.25.1.el6, kernel-abi-whitelists 2.6.32-754.25.1.el6, kernel-debuginfo-common-i686 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6 Red Hat Enterprise Linux Desktop Optional (v. 6) python-perf 2.6.32-754.25.1.el6, kernel-debuginfo-common-i686 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4256
  • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) perf 4.14.0-115.16.1.el7a, kernel 4.14.0-115.16.1.el7a, kernel-alt 4.14.0-115.16.1.el7a, python-perf 4.14.0-115.16.1.el7a, kernel-tools 4.14.0-115.16.1.el7a, kernel-tools-libs 4.14.0-115.16.1.el7a, +3 more Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) kernel-debuginfo-common-ppc64le 4.14.0-115.16.1.el7a
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4154
  • Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-kvm 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-trace 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-debug-kvm 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-trace-kvm 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1062.7.1.rt56.1030.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3978
  • Red Hat Enterprise Linux HPC Node (v. 6) perf 2.6.32-754.25.1.el6, kernel 2.6.32-754.25.1.el6, kernel-firmware 2.6.32-754.25.1.el6, kernel-abi-whitelists 2.6.32-754.25.1.el6, kernel-debuginfo-common-i686 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6 Red Hat Enterprise Linux HPC Node Optional (v. 6) python-perf 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4256
  • Red Hat Enterprise Linux Real Time (v. 8) kernel-rt 4.18.0-147.rt24.93.el8, kernel-rt-core 4.18.0-147.rt24.93.el8, kernel-rt-modules 4.18.0-147.rt24.93.el8, kernel-rt-debug-core 4.18.0-147.rt24.93.el8, kernel-rt-debug-modules 4.18.0-147.rt24.93.el8, kernel-rt-modules-extra 4.18.0-147.rt24.93.el8, +2 more Red Hat Enterprise Linux Real Time for NFV (v. 8) kernel-rt 4.18.0-147.rt24.93.el8, kernel-rt-kvm 4.18.0-147.rt24.93.el8, kernel-rt-core 4.18.0-147.rt24.93.el8, kernel-rt-modules 4.18.0-147.rt24.93.el8, kernel-rt-debug-kvm 4.18.0-147.rt24.93.el8, kernel-rt-debug-core 4.18.0-147.rt24.93.el8, +4 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3309
  • Red Hat Enterprise Linux Realtime (v. 7) kernel-rt 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-trace 3.10.0-1062.7.1.rt56.1030.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-1062.7.1.rt56.1030.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3978
  • Red Hat Enterprise Linux Server (v. 6) perf 2.6.32-754.25.1.el6, kernel 2.6.32-754.25.1.el6, kernel-kdump 2.6.32-754.25.1.el6, kernel-firmware 2.6.32-754.25.1.el6, kernel-bootwrapper 2.6.32-754.25.1.el6, kernel-abi-whitelists 2.6.32-754.25.1.el6, +4 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4256
  • Red Hat Enterprise Linux Server (v. 7) perf 3.10.0-1062.7.1.el7, kernel 3.10.0-1062.7.1.el7, bpftool 3.10.0-1062.7.1.el7, python-perf 3.10.0-1062.7.1.el7, kernel-kdump 3.10.0-1062.7.1.el7, kernel-tools 3.10.0-1062.7.1.el7, +13 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3979
  • Red Hat Enterprise Linux Server EUS (v. 7.6) perf 3.10.0-957.56.1.el7, kernel 3.10.0-957.56.1.el7, bpftool 3.10.0-957.56.1.el7, python-perf 3.10.0-957.56.1.el7, kernel-kdump 3.10.0-957.56.1.el7, kernel-tools 3.10.0-957.56.1.el7, +7 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2020:2851
  • Red Hat Enterprise Linux Server Optional (v. 6) python-perf 2.6.32-754.25.1.el6, kernel-debuginfo-common-i686 2.6.32-754.25.1.el6, kernel-debuginfo-common-ppc64 2.6.32-754.25.1.el6, kernel-debuginfo-common-s390x 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4256
  • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debuginfo-common-ppc64 3.10.0-1062.7.1.el7, kernel-debuginfo-common-x86_64 3.10.0-1062.7.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-1062.7.1.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3979
  • Red Hat Enterprise Linux Server Optional EUS (v. 7.6) kernel-debuginfo-common-ppc64 3.10.0-957.56.1.el7, kernel-debuginfo-common-x86_64 3.10.0-957.56.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-957.56.1.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2020:2851
  • Red Hat Enterprise Linux Workstation (v. 6) perf 2.6.32-754.25.1.el6, kernel 2.6.32-754.25.1.el6, kernel-firmware 2.6.32-754.25.1.el6, kernel-abi-whitelists 2.6.32-754.25.1.el6, kernel-debuginfo-common-i686 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4256
  • Red Hat Enterprise Linux Workstation (v. 7) perf 3.10.0-1062.7.1.el7, kernel 3.10.0-1062.7.1.el7, bpftool 3.10.0-1062.7.1.el7, python-perf 3.10.0-1062.7.1.el7, kernel-tools 3.10.0-1062.7.1.el7, kernel-tools-libs 3.10.0-1062.7.1.el7, +2 more
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3979
  • Red Hat Enterprise Linux Workstation Optional (v. 6) python-perf 2.6.32-754.25.1.el6, kernel-debuginfo-common-i686 2.6.32-754.25.1.el6, kernel-debuginfo-common-x86_64 2.6.32-754.25.1.el6
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:4256
  • Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-1062.7.1.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2019:3979
  • Red Hat Virtualization 4.2 Hypervisor for RHEL 7.6 EUS perf 3.10.0-957.56.1.el7, python-perf 3.10.0-957.56.1.el7
    fixed: vendor fix “Restrict access to the '/dev/kvm' device to trusted users.” RHSA-2020:2851
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) kernel-headers 3.10.0-957.56.1.el7 Red Hat Enterprise Linux Server EUS (v. 7.6) kernel-headers 3.10.0-957.56.1.el7 Red Hat Enterprise MRG 2 kernel-rt, mrg-rt-release, kernel-rt-trace, kernel-rt-vanilla, kernel-rt-firmware Red Hat Virtualization 4.2 Hypervisor for RHEL 7.6 EUS kernel-headers 3.10.0-957.56.1.el7
    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

Exploit prediction

0.76% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.0 7.5 CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:H
NVD 3.1 8.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
NVD 2.0 7.2 AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

  • Linux Kernel

Classification

Weakness
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.