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Fencer Vulns
medium 5.5

CVE-2017-18344 json

The timer_create syscall implementation in kernel/time/posix-timers.c in the Linux kernel before 4.14.8 doesn't properly validate the sigev…

published 2018-07-26 8 y ago modified 2026-06-17 4 mo ago also EUVD-2017-9469

cvss
5.5
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
3.4%
EPSS 3.4% chance of exploitation in 30 days, percentile 89%
public exploits
1
Exploit-DB

Summary

The timer_create syscall implementation in kernel/time/posix-timers.c in the Linux kernel before 4.14.8 doesn't properly validate the sigevent->sigev_notify field, which leads to out-of-bounds access in the show_timer function (called when /proc/$PID/timers is read). This allows userspace applications to read arbitrary kernel memory (on a kernel built with CONFIG_POSIX_TIMERS and CONFIG_CHECKPOINT_RESTORE).

Patch / fix

  • linux linux_kernel 4.14.8
  • linux Debian 14, Debian 13, Debian 12 4.14.12-1

debian advisories DEBIAN-CVE-2017-18344

  • linux Ubuntu 14.04 LTS 3.13.0-155.205
  • linux Ubuntu 16.04 LTS 4.4.0-121.145
  • linux-aws Ubuntu 14.04 LTS 4.4.0-1017.17
  • linux-aws Ubuntu 16.04 LTS 4.4.0-1055.64
  • linux-gcp Ubuntu 16.04 LTS 4.15.0-1014.14~16.04.1
  • linux-hwe Ubuntu 16.04 LTS 4.15.0-24.26~16.04.1
  • linux-kvm Ubuntu 16.04 LTS 4.4.0-1021.26
  • linux-azure Ubuntu 16.04 LTS 4.15.0-1013.13~16.04.2

ubuntu advisories UBUNTU-CVE-2017-18344

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-alt RHEL 7 4.14.0-115.el7a
  • perf RHEL 7 4.14.0-115.el7a
  • kernel RHEL 7 4.14.0-115.el7a
  • python-perf RHEL 7 4.14.0-115.el7a
  • kernel-tools RHEL 7 4.14.0-115.el7a
  • kernel-tools-libs RHEL 7 4.14.0-115.el7a
  • kernel-bootwrapper RHEL 7 4.14.0-115.el7a
  • kernel-abi-whitelists RHEL 7 4.14.0-115.el7a

red hat advisories RHSA-2018:2948RHSA-2018:3096RHSA-2018:3083RHSA-2018:3590RHSA-2018:3586RHSA-2018:3540

  • kernel-syms SLES 12 SP2-BCL, OpenStack Cloud 7, Enterprise Storage 4 +2 more 4.4.121-92.92.1
  • kernel-source SLES 12 SP2-BCL, OpenStack Cloud 7, Enterprise Storage 4 +2 more 4.4.121-92.92.1
  • lttng-modules SLES 12 SP2-BCL, OpenStack Cloud 7, Enterprise Storage 4 +2 more 2.7.1-9.4.1
  • kernel-default SLES 12 SP2-BCL, SLE High Availability Extension 12 SP2, OpenStack Cloud 7 +3 more 4.4.121-92.92.1
  • kgraft-patch-SLE12-SP2_Update_24 SLES 12 SP2-BCL, OpenStack Cloud 7, Enterprise Storage 4 +2 more 1-3.7.1
  • kernel-rt SLE Real Time 12 SP3 4.4.147-3.20.1
  • kernel-syms-rt SLE Real Time 12 SP3 4.4.147-3.20.1
  • kernel-rt_debug SLE Real Time 12 SP3 4.4.147-3.20.1

suse advisories SUSE-SU-2023:3333-1SUSE-SU-2018:2344-2SUSE-SU-2018:2596-1SUSE-SU-2018:2474-1SUSE-SU-2018:2472-1SUSE-SU-2018:2413-1

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-2017-18344 updated cvss 7.1

kernel: out-of-bounds access in the show_timer function in kernel/time/posix-timers.c

  • Red Hat Enterprise Linux Client (v. 7) perf 3.10.0-957.el7, kernel 3.10.0-957.el7, bpftool 3.10.0-957.el7, python-perf 3.10.0-957.el7, kernel-tools 3.10.0-957.el7, kernel-tools-libs 3.10.0-957.el7, +2 more Red Hat Enterprise Linux Client Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-957.el7 Red Hat Enterprise Linux ComputeNode (v. 7) perf 3.10.0-957.el7, kernel 3.10.0-957.el7, bpftool 3.10.0-957.el7, python-perf 3.10.0-957.el7, kernel-tools 3.10.0-957.el7, kernel-tools-libs 3.10.0-957.el7, +2 more
    fixed: vendor fix RHSA-2018:3083
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.3) perf 3.10.0-514.61.1.el7, kernel 3.10.0-514.61.1.el7, python-perf 3.10.0-514.61.1.el7, kernel-tools 3.10.0-514.61.1.el7, kernel-tools-libs 3.10.0-514.61.1.el7, kernel-abi-whitelists 3.10.0-514.61.1.el7, +1 more
    fixed: vendor fix RHSA-2018:3591
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.4) perf 3.10.0-693.43.1.el7, kernel 3.10.0-693.43.1.el7, python-perf 3.10.0-693.43.1.el7, kernel-tools 3.10.0-693.43.1.el7, kernel-tools-libs 3.10.0-693.43.1.el7, kernel-abi-whitelists 3.10.0-693.43.1.el7, +1 more
    fixed: vendor fix RHSA-2018:3540
  • Red Hat Enterprise Linux ComputeNode EUS (v. 7.5) perf 3.10.0-862.20.2.el7, kernel 3.10.0-862.20.2.el7, python-perf 3.10.0-862.20.2.el7, kernel-tools 3.10.0-862.20.2.el7, kernel-tools-libs 3.10.0-862.20.2.el7, kernel-abi-whitelists 3.10.0-862.20.2.el7, +1 more
    fixed: vendor fix RHSA-2018:3459
  • Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-957.el7
    fixed: vendor fix RHSA-2018:3083
  • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.3) kernel-debuginfo-common-x86_64 3.10.0-514.61.1.el7
    fixed: vendor fix RHSA-2018:3591
  • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.4) kernel-debuginfo-common-x86_64 3.10.0-693.43.1.el7
    fixed: vendor fix RHSA-2018:3540
  • Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.5) kernel-debuginfo-common-x86_64 3.10.0-862.20.2.el7
    fixed: vendor fix RHSA-2018:3459
show 16 more
  • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) perf 3.10.0-957.el7, perf 4.14.0-115.el7a, kernel 3.10.0-957.el7, kernel 4.14.0-115.el7a, kernel-alt 4.14.0-115.el7a, python-perf 3.10.0-957.el7, +13 more Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) kernel-debuginfo-common-ppc64le 3.10.0-957.el7, kernel-debuginfo-common-ppc64le 4.14.0-115.el7a
    fixed: vendor fix RHSA-2018:3083
  • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt 3.10.0-957.rt56.910.el7, kernel-rt-trace 3.10.0-957.rt56.910.el7 Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt 3.10.0-957.rt56.910.el7, kernel-rt-kvm 3.10.0-957.rt56.910.el7, kernel-rt-trace 3.10.0-957.rt56.910.el7, kernel-rt-debug-kvm 3.10.0-957.rt56.910.el7, kernel-rt-trace-kvm 3.10.0-957.rt56.910.el7, kernel-rt-debuginfo-common-x86_64 3.10.0-957.rt56.910.el7
    fixed: vendor fix RHSA-2018:3096
  • Red Hat Enterprise Linux Server (v. 7) perf 3.10.0-957.el7, kernel 3.10.0-957.el7, bpftool 3.10.0-957.el7, python-perf 3.10.0-957.el7, kernel-kdump 3.10.0-957.el7, kernel-tools 3.10.0-957.el7, +7 more
    fixed: vendor fix RHSA-2018:3083
  • Red Hat Enterprise Linux Server AUS (v. 7.2) perf 3.10.0-327.76.1.el7, kernel 3.10.0-327.76.1.el7, python-perf 3.10.0-327.76.1.el7, kernel-tools 3.10.0-327.76.1.el7, kernel-tools-libs 3.10.0-327.76.1.el7, kernel-abi-whitelists 3.10.0-327.76.1.el7, +1 more Red Hat Enterprise Linux Server E4S (v. 7.2) perf 3.10.0-327.76.1.el7, kernel 3.10.0-327.76.1.el7, python-perf 3.10.0-327.76.1.el7, kernel-tools 3.10.0-327.76.1.el7, kernel-tools-libs 3.10.0-327.76.1.el7, kernel-abi-whitelists 3.10.0-327.76.1.el7, +1 more
    fixed: vendor fix RHSA-2018:3590
  • Red Hat Enterprise Linux Server EUS (v. 7.3) perf 3.10.0-514.61.1.el7, kernel 3.10.0-514.61.1.el7, python-perf 3.10.0-514.61.1.el7, kernel-kdump 3.10.0-514.61.1.el7, kernel-tools 3.10.0-514.61.1.el7, kernel-tools-libs 3.10.0-514.61.1.el7, +6 more
    fixed: vendor fix RHSA-2018:3591
  • Red Hat Enterprise Linux Server EUS (v. 7.4) perf 3.10.0-693.43.1.el7, kernel 3.10.0-693.43.1.el7, python-perf 3.10.0-693.43.1.el7, kernel-kdump 3.10.0-693.43.1.el7, kernel-tools 3.10.0-693.43.1.el7, kernel-tools-libs 3.10.0-693.43.1.el7, +6 more
    fixed: vendor fix RHSA-2018:3540
  • Red Hat Enterprise Linux Server EUS (v. 7.5) perf 3.10.0-862.20.2.el7, kernel 3.10.0-862.20.2.el7, python-perf 3.10.0-862.20.2.el7, kernel-kdump 3.10.0-862.20.2.el7, kernel-tools 3.10.0-862.20.2.el7, kernel-tools-libs 3.10.0-862.20.2.el7, +6 more
    fixed: vendor fix RHSA-2018:3459
  • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debuginfo-common-ppc64 3.10.0-957.el7, kernel-debuginfo-common-x86_64 3.10.0-957.el7, kernel-debuginfo-common-ppc64le 3.10.0-957.el7
    fixed: vendor fix RHSA-2018:3083
  • Red Hat Enterprise Linux Server Optional AUS (v. 7.2) kernel-debuginfo-common-x86_64 3.10.0-327.76.1.el7 Red Hat Enterprise Linux Server Optional E4S (v. 7.2) kernel-debuginfo-common-x86_64 3.10.0-327.76.1.el7
    fixed: vendor fix RHSA-2018:3590
  • Red Hat Enterprise Linux Server Optional EUS (v. 7.3) kernel-debuginfo-common-ppc64 3.10.0-514.61.1.el7, kernel-debuginfo-common-x86_64 3.10.0-514.61.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-514.61.1.el7
    fixed: vendor fix RHSA-2018:3591
  • Red Hat Enterprise Linux Server Optional EUS (v. 7.4) kernel-debuginfo-common-ppc64 3.10.0-693.43.1.el7, kernel-debuginfo-common-x86_64 3.10.0-693.43.1.el7, kernel-debuginfo-common-ppc64le 3.10.0-693.43.1.el7
    fixed: vendor fix RHSA-2018:3540
  • Red Hat Enterprise Linux Server Optional EUS (v. 7.5) kernel-debuginfo-common-ppc64 3.10.0-862.20.2.el7, kernel-debuginfo-common-x86_64 3.10.0-862.20.2.el7, kernel-debuginfo-common-ppc64le 3.10.0-862.20.2.el7
    fixed: vendor fix RHSA-2018:3459
  • Red Hat Enterprise Linux Server Optional TUS (v. 7.2) kernel-debuginfo-common-x86_64 3.10.0-327.76.1.el7 Red Hat Enterprise Linux Server TUS (v. 7.2) perf 3.10.0-327.76.1.el7, kernel 3.10.0-327.76.1.el7, python-perf 3.10.0-327.76.1.el7, kernel-tools 3.10.0-327.76.1.el7, kernel-tools-libs 3.10.0-327.76.1.el7, kernel-abi-whitelists 3.10.0-327.76.1.el7, +1 more
    fixed: vendor fix RHSA-2018:3590
  • Red Hat Enterprise Linux Workstation (v. 7) perf 3.10.0-957.el7, kernel 3.10.0-957.el7, bpftool 3.10.0-957.el7, python-perf 3.10.0-957.el7, kernel-tools 3.10.0-957.el7, kernel-tools-libs 3.10.0-957.el7, +2 more Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-debuginfo-common-x86_64 3.10.0-957.el7
    fixed: vendor fix RHSA-2018:3083
  • Red Hat MRG Realtime for RHEL 6 Server v.2 kernel-rt 3.10.0-693.43.1.rt56.630.el6rt, kernel-rt-trace 3.10.0-693.43.1.rt56.630.el6rt, kernel-rt-vanilla 3.10.0-693.43.1.rt56.630.el6rt, kernel-rt-firmware 3.10.0-693.43.1.rt56.630.el6rt, kernel-rt-debuginfo-common-x86_64 3.10.0-693.43.1.rt56.630.el6rt
    fixed: vendor fix RHSA-2018:3586
  • Red Hat Enterprise Linux 5 kernel Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-core, kernel-tools, python3-perf, +17 more Red Hat Enterprise Linux Client (v. 7) kernel-headers 3.10.0-957.el7 Red Hat Enterprise Linux ComputeNode (v. 7) kernel-headers 3.10.0-957.el7 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) kernel-headers 3.10.0-957.el7
    +2 more products
    Red Hat Enterprise Linux Server (v. 7) kernel-headers 3.10.0-957.el7 Red Hat Enterprise Linux Workstation (v. 7) kernel-headers 3.10.0-957.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

Timeline

  1. Published
  2. First public exploit (EDB-45175)

Exploit prediction

3.44% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • EDB-45175 Linux Kernel 4.14.7 (Ubuntu 16.04 / CentOS 7) - (KASLR & SMEP Bypass) Arbitrary File Read local, 2018-08-09

CVSS scores

assigned by version score vector
NVD 3.0 5.5 CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N

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.