CVE-2018-14599

Name: CVE-2018-14599
Creator: NVD / NIST
Published: 2018-08-24T19:29:01.457+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 4.99%

Last modified Jun 17, 2026

CVE-2018-14599 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. An issue was discovered in libX11 through 1.6.5. The function XListExtensions in ListExt.c is vulnerable to an off-by-one error caused by malicious server responses, leading to DoS or possibly unspecified other impact.. EPSS estimates a 4.99% chance of exploitation in the next 30 days.

Description

An issue was discovered in libX11 through 1.6.5. The function XListExtensions in ListExt.c is vulnerable to an off-by-one error caused by malicious server responses, leading to DoS or possibly unspecified other impact.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

4.99%

91.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-193

Affected Software

Vendor	Product	Versions
X.Org	Libx11	<= 1.6.5
Canonical	Ubuntu Linux	12.04
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Debian	Debian Linux	8.0
Fedoraproject	Fedora	28
Redhat	Enterprise Linux Desktop	7.0
Redhat	Enterprise Linux Server	7.0
Redhat	Enterprise Linux Workstation	7.0

References

http://www.openwall.com/lists/oss-security/2018/08/21/6Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/105177Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1041543Third Party Advisory, VDB Entry
https://access.redhat.com/errata/RHSA-2019:2079Third Party Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1102062Issue Tracking, Patch, Third Party Advisory
https://cgit.freedesktop.org/xorg/lib/libX11/commit/?id=b469da1430cdcee06e31c6251b83aede072a1ff0Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/08/msg00030.htmlThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YGARUV66TS5OOSLR5A76BUB7SDV6GO4F/
https://lists.x.org/archives/xorg-announce/2018-August/002916.htmlThird Party Advisory
https://security.gentoo.org/glsa/201811-01Third Party Advisory
https://usn.ubuntu.com/3758-1/Third Party Advisory
https://usn.ubuntu.com/3758-2/Third Party Advisory
http://www.openwall.com/lists/oss-security/2018/08/21/6Mailing List, Third Party Advisory
http://www.securityfocus.com/bid/105177Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1041543Third Party Advisory, VDB Entry
https://access.redhat.com/errata/RHSA-2019:2079Third Party Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1102062Issue Tracking, Patch, Third Party Advisory
https://cgit.freedesktop.org/xorg/lib/libX11/commit/?id=b469da1430cdcee06e31c6251b83aede072a1ff0Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/08/msg00030.htmlThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YGARUV66TS5OOSLR5A76BUB7SDV6GO4F/
https://lists.x.org/archives/xorg-announce/2018-August/002916.htmlThird Party Advisory
https://security.gentoo.org/glsa/201811-01Third Party Advisory
https://usn.ubuntu.com/3758-1/Third Party Advisory
https://usn.ubuntu.com/3758-2/Third Party Advisory

Timeline

Published: Aug 24, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-14599?

How severe is CVE-2018-14599?

CVE-2018-14599 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 4.99% probability of exploitation in the next 30 days.

How do I fix CVE-2018-14599?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-14599?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST