Skip to content
Fencer Intel
medium 5.9

CVE-2018-12232 json

In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the sam…

published 2018-06-12 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-4210

cvss
5.9
version 3.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
6.3%
EPSS 6.3% chance of exploitation in 30 days, percentile 93%
public exploits
0
none known

Summary

In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the same socket file descriptor, related to the sock_close and sockfs_setattr functions. fchownat does not increment the file descriptor reference count, which allows close to set the socket to NULL during fchownat's execution, leading to a NULL pointer dereference and system crash.

Patch / fix

  • linux Debian 14, Debian 13, Debian 12 4.17.3-1

debian advisories DEBIAN-CVE-2018-12232

  • linux Ubuntu 18.04 LTS 4.15.0-33.36
  • linux-aws Ubuntu 18.04 LTS 4.15.0-1020.20
  • linux-gcp Ubuntu 16.04 LTS 4.15.0-1018.19~16.04.2
  • linux-gcp Ubuntu 18.04 LTS 4.15.0-1018.19
  • linux-hwe Ubuntu 16.04 LTS 4.15.0-33.36~16.04.1
  • linux-kvm Ubuntu 18.04 LTS 4.15.0-1020.20
  • linux-oem Ubuntu 18.04 LTS 4.15.0-1017.20
  • linux-azure Ubuntu 16.04 LTS 4.15.0-1022.22~16.04.1

ubuntu advisories UBUNTU-CVE-2018-12232

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-2018:2948

  • kernel-syms SLE Module for Development Tools 15 4.12.14-25.28.1
  • kernel-source SLE Module for Development Tools 15, SLE Module for Basesystem 15 4.12.14-25.28.1
  • kernel-default SLE Workstation Extension 15, SLE Module for Legacy 15, SLE Module for Basesystem 15 +2 more 4.12.14-25.28.1
  • kernel-vanilla SLE Module for Development Tools 15 4.12.14-25.28.1
  • kernel-zfcpdump SLE Module for Basesystem 15 4.12.14-25.28.1
  • kernel-obs-build SLE Module for Development Tools 15 4.12.14-25.28.1
  • kernel-azure SLES for SAP 12 SP4, SLES 12 SP4 4.12.14-6.6.2
  • kernel-syms-azure SLES for SAP 12 SP4, SLES 12 SP4 4.12.14-6.6.2

suse advisories SUSE-SU-2019:0740-1SUSE-SU-2019:0224-1SUSE-SU-2019:0222-1SUSE-SU-2019:0196-1SUSE-SU-2019:0150-1

  • kernel-source openSUSE Tumbleweed 5.14.6-1.4
  • kernel-source openSUSE Tumbleweed 6.6.17-1.1
  • kernel-source openSUSE Leap 15.0 4.12.14-lp150.12.45.1

opensuse advisories openSUSE-SU-2024:10728-1openSUSE-SU-2024:13704-1openSUSE-SU-2019:0065-1

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-2018-12232 updated cvss 5.5

kernel: NULL pointer dereference if close and fchownat system calls share a socket file descriptor

  • Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) perf 4.14.0-115.el7a, kernel 4.14.0-115.el7a, kernel-alt 4.14.0-115.el7a, python-perf 4.14.0-115.el7a, kernel-tools 4.14.0-115.el7a, kernel-tools-libs 4.14.0-115.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.el7a
    fixed: vendor fix RHSA-2018:2948
  • 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 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-core, kernel-tools, python3-perf, +17 more Red Hat Enterprise MRG 2 kernel-rt, mrg-rt-release, kernel-rt-trace, kernel-rt-vanilla, kernel-rt-firmware
    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

6.30% chance of exploitation in the next 30 days, higher than 93% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.0 5.9 CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 7.1 AV:N/AC:M/Au:N/C:N/I:N/A:C

Classification

Weakness
  • CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization
Technology feeds

References

Sources

Fencer Intel 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.