How severe is CVE-2018-14598?

CVE-2018-14598 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-14598 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-14598?

CVE-2018-14598 primarily affects X.org Libx11. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-14598?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-14598 published?

CVE-2018-14598 was published on 2018-08-24 and last updated on 2026-06-17.

CVE-2018-14598

CVE-2018-14598 is a high-severity vulnerability in X.org Libx11 with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: X.org Libx11
Published: 2018-08-24
Last modified: 2026-06-17

Description

An issue was discovered in XListExtensions in ListExt.c in libX11 through 1.6.5. A malicious server can send a reply in which the first string overflows, causing a variable to be set to NULL that will be freed later on, leading to DoS (segmentation fault).

Frequently asked questions

What is CVE-2018-14598?: An issue was discovered in XListExtensions in ListExt.c in libX11 through 1.6.5. A malicious server can send a reply in which the first string overflows, causing a variable to be set to NULL that will be freed later on, leading to DoS (segmentation fault).
How severe is CVE-2018-14598?: CVE-2018-14598 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-14598 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-14598?: CVE-2018-14598 primarily affects X.org Libx11. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-14598?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-14598 published?: CVE-2018-14598 was published on 2018-08-24 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:x.org:libx11:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:28:*:*:*:*:*:*:*

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