medium 4.3

CVE-2018-16866 json

An out of bounds read was discovered in systemd-journald in the way it parses log messages that terminate with a colon ':'. A local attacke…

published 2019-01-11 7 y ago modified 2026-06-17 4 mo ago also EUVD-2018-8657

cvss: 4.3; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 64%
public exploits: 0; none known

An out of bounds read was discovered in systemd-journald in the way it parses log messages that terminate with a colon ':'. A local attacker can use this flaw to disclose process memory data. Versions from v221 to v239 are vulnerable.

Patch / fix

distros 6 links 1

debian ubuntu red hat suse opensuse arch linux

systemd Debian 14, Debian 13, Debian 12 240-1

debian advisories DEBIAN-CVE-2018-16866

systemd Ubuntu 16.04 LTS 229-4ubuntu21.15
systemd Ubuntu 18.04 LTS 237-3ubuntu10.11

ubuntu advisories UBUNTU-CVE-2018-16866

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

systemd RHEL 7 219-67.el7
libgudev1 RHEL 7 219-67.el7
systemd-libs RHEL 7 219-67.el7
systemd-sysv RHEL 7 219-67.el7
systemd-python RHEL 7 219-67.el7
systemd-networkd RHEL 7 219-67.el7
systemd-resolved RHEL 7 219-67.el7
systemd-journal-gateway RHEL 7 219-67.el7

red hat advisories RHSA-2020:1264 RHSA-2020:0593 RHSA-2019:3222 RHSA-2019:2091

systemd SLE Module for Basesystem 15 234-24.20.1
systemd SLES for SAP 12 SP4, SLES for SAP 12 SP3, SLES for SAP 12 SP2 +10 more 228-150.58.1

suse advisories SUSE-SU-2019:0137-1 SUSE-SU-2019:0135-1

systemd openSUSE Leap 15.0 234-lp150.20.12.1
systemd-mini openSUSE Leap 15.0 234-lp150.20.12.1

opensuse advisories openSUSE-SU-2019:0098-1

systemd Arch Linux 240.0-3

arch linux advisories AVG-615

bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16866 advisory

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-2018-16866 updated 2026-11-05 cvss 4.3

systemd: out-of-bounds read when parsing a crafted syslog message

Red Hat Virtualization 4 rhvm-appliance, redhat-virtualization-host-image-update
affected: no fix planned “Will not fix”
Red Hat Ansible Tower 3.4 for RHEL 7 Server ansible-tower-34/ansible-tower-memcached 1.4.15-28, ansible-tower-35/ansible-tower-memcached 1.4.15-28, ansible-tower-37/ansible-tower-memcached-rhel7 1.4.15-28
fixed: vendor fix RHBA-2020:0547
Red Hat Enterprise Linux Client (v. 7) systemd 219-67.el7, libgudev1 219-67.el7, systemd-libs 219-67.el7, systemd-sysv 219-67.el7, systemd-python 219-67.el7 Red Hat Enterprise Linux Client Optional (v. 7) systemd-networkd 219-67.el7, systemd-resolved 219-67.el7, systemd-journal-gateway 219-67.el7 Red Hat Enterprise Linux ComputeNode (v. 7) systemd 219-67.el7, libgudev1 219-67.el7, systemd-libs 219-67.el7, systemd-sysv 219-67.el7, systemd-python 219-67.el7
fixed: vendor fix RHSA-2019:2091
Red Hat Enterprise Linux ComputeNode EUS (v. 7.5) systemd 219-57.el7_5.9, libgudev1 219-57.el7_5.9, systemd-libs 219-57.el7_5.9, systemd-sysv 219-57.el7_5.9, systemd-python 219-57.el7_5.9
fixed: vendor fix RHSA-2020:1264
Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) systemd 219-62.el7_6.11, libgudev1 219-62.el7_6.11, systemd-libs 219-62.el7_6.11, systemd-sysv 219-62.el7_6.11, systemd-python 219-62.el7_6.11
fixed: vendor fix RHSA-2019:3222
Red Hat Enterprise Linux ComputeNode Optional (v. 7) systemd-networkd 219-67.el7, systemd-resolved 219-67.el7, systemd-journal-gateway 219-67.el7
fixed: vendor fix RHSA-2019:2091
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.5) systemd-networkd 219-57.el7_5.9, systemd-resolved 219-57.el7_5.9, systemd-journal-gateway 219-57.el7_5.9
fixed: vendor fix RHSA-2020:1264
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) systemd-networkd 219-62.el7_6.11, systemd-resolved 219-62.el7_6.11, systemd-journal-gateway 219-62.el7_6.11 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) systemd 219-62.el7_6.11, libgudev1 219-62.el7_6.11, systemd-libs 219-62.el7_6.11, systemd-sysv 219-62.el7_6.11, systemd-python 219-62.el7_6.11 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) systemd-networkd 219-62.el7_6.11, systemd-resolved 219-62.el7_6.11, systemd-journal-gateway 219-62.el7_6.11
fixed: vendor fix RHSA-2019:3222

show 11 more

Red Hat Enterprise Linux Server (v. 7) systemd 219-67.el7, libgudev1 219-67.el7, systemd-libs 219-67.el7, systemd-sysv 219-67.el7, systemd-python 219-67.el7
fixed: vendor fix RHSA-2019:2091
Red Hat Enterprise Linux Server AUS (v. 7.4) systemd 219-42.el7_4.20, libgudev1 219-42.el7_4.20, systemd-libs 219-42.el7_4.20, systemd-sysv 219-42.el7_4.20, systemd-python 219-42.el7_4.20 Red Hat Enterprise Linux Server E4S (v. 7.4) systemd 219-42.el7_4.20, libgudev1 219-42.el7_4.20, systemd-libs 219-42.el7_4.20, systemd-sysv 219-42.el7_4.20, systemd-python 219-42.el7_4.20
fixed: vendor fix RHSA-2020:0593
Red Hat Enterprise Linux Server EUS (v. 7.5) systemd 219-57.el7_5.9, libgudev1 219-57.el7_5.9, systemd-libs 219-57.el7_5.9, systemd-sysv 219-57.el7_5.9, systemd-python 219-57.el7_5.9
fixed: vendor fix RHSA-2020:1264
Red Hat Enterprise Linux Server EUS (v. 7.6) systemd 219-62.el7_6.11, libgudev1 219-62.el7_6.11, systemd-libs 219-62.el7_6.11, systemd-sysv 219-62.el7_6.11, systemd-python 219-62.el7_6.11
fixed: vendor fix RHSA-2019:3222
Red Hat Enterprise Linux Server Optional (v. 7) systemd-networkd 219-67.el7, systemd-resolved 219-67.el7, systemd-journal-gateway 219-67.el7
fixed: vendor fix RHSA-2019:2091
Red Hat Enterprise Linux Server Optional AUS (v. 7.4) systemd-networkd 219-42.el7_4.20, systemd-resolved 219-42.el7_4.20, systemd-journal-gateway 219-42.el7_4.20 Red Hat Enterprise Linux Server Optional E4S (v. 7.4) systemd-networkd 219-42.el7_4.20, systemd-resolved 219-42.el7_4.20, systemd-journal-gateway 219-42.el7_4.20
fixed: vendor fix RHSA-2020:0593
Red Hat Enterprise Linux Server Optional EUS (v. 7.5) systemd-networkd 219-57.el7_5.9, systemd-resolved 219-57.el7_5.9, systemd-journal-gateway 219-57.el7_5.9
fixed: vendor fix RHSA-2020:1264
Red Hat Enterprise Linux Server Optional EUS (v. 7.6) systemd-networkd 219-62.el7_6.11, systemd-resolved 219-62.el7_6.11, systemd-journal-gateway 219-62.el7_6.11
fixed: vendor fix RHSA-2019:3222
Red Hat Enterprise Linux Server Optional TUS (v. 7.4) systemd-networkd 219-42.el7_4.20, systemd-resolved 219-42.el7_4.20, systemd-journal-gateway 219-42.el7_4.20 Red Hat Enterprise Linux Server TUS (v. 7.4) systemd 219-42.el7_4.20, libgudev1 219-42.el7_4.20, systemd-libs 219-42.el7_4.20, systemd-sysv 219-42.el7_4.20, systemd-python 219-42.el7_4.20
fixed: vendor fix RHSA-2020:0593
Red Hat Enterprise Linux Workstation (v. 7) systemd 219-67.el7, libgudev1 219-67.el7, systemd-libs 219-67.el7, systemd-sysv 219-67.el7, systemd-python 219-67.el7 Red Hat Enterprise Linux Workstation Optional (v. 7) systemd-networkd 219-67.el7, systemd-resolved 219-67.el7, systemd-journal-gateway 219-67.el7
fixed: vendor fix RHSA-2019:2091
Red Hat Enterprise Linux 8 systemd, systemd-pam, systemd-libs, systemd-udev, systemd-tests, systemd-container, +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: 17 mo ago (2025-06-09)

Exploit prediction

1.05% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

qualys.com https://www.qualys.com/2019/01/09/system-down/system-down.txt referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.0	4.3	CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD	3.1	3.3	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
NVD	2.0	2.1	AV:L/AC:L/Au:N/C:P/I:N/A:N

Affected products

The systemd Project systemd

Classification

Weakness

CWE-125 Out-of-bounds Read
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

bugzilla.redhat.com /show_bug.cgi?id=CVE-2018-16866
issue-tracking, patch, third-party-advisory
qualys.com /2019/01/09/system-down/system-down.txt
exploit, third-party-advisory
debian.org /security/2019/dsa-4367
vendor-advisory, third-party-advisory
usn.ubuntu.com /3855-1/
vendor-advisory, third-party-advisory
security.gentoo.org /glsa/201903-07
vendor-advisory, third-party-advisory
access.redhat.com /errata/RHSA-2019:2091
vendor-advisory, third-party-advisory
access.redhat.com /errata/RHSA-2019:3222
vendor-advisory, third-party-advisory
access.redhat.com /errata/RHSA-2020:0593
vendor-advisory, third-party-advisory
security.netapp.com /advisory/ntap-20190117-0001/
third-party-advisory
securityfocus.com /bid/106527
vdb-entry, third-party-advisory
openwall.com /lists/oss-security/2019/05/10/4
mailing-list, third-party-advisory
seclists.org /bugtraq/2019/May/25
mailing-list, third-party-advisory
packetstormsecurity.com /files/152841/System-Down-A-systemd-journald-Exploit.html
third-party-advisory, vdb-entry
seclists.org /fulldisclosure/2019/May/21
mailing-list, third-party-advisory

Sources

CVE List CVE-2018-16866
NVD CVE-2018-16866

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.

Summary