What is CVE-2020-14345?

CVE-2020-14345 is a high-severity vulnerability in X.org X Server, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2020-09-15.

How severe is CVE-2020-14345?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2020-14345 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in X.org X Server

CVE-2020-14345

A flaw was found in X.Org Server before xorg-x11-server 1.20.9. An Out-Of-Bounds access in XkbSetNames function may lead to a privilege escalation vulnerability. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Vulnerability class: Buffer Overflow

Published 2020-09-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (46.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

X.org X Server
Canonical Ubuntu Linux — versions 14.04, 16.04, 18.04
Xorg-X11-Server — versions before xorg-x11-server 1.20.9

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

Live-Hack-CVE/CVE-2020-14345

References

bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
lists.x.org/archives/xorg-announce/2020-August/003058.html (Vendor Advisory)
usn.ubuntu.com/4490-1/ (vendor-advisory, Third Party Advisory)
usn.ubuntu.com/4488-2/ (vendor-advisory, Third Party Advisory)
security.gentoo.org/glsa/202012-01 (vendor-advisory, Third Party Advisory)
www.zerodayinitiative.com/advisories/ZDI-20-1416/ (VDB Entry, Third Party Advisory)
www.openwall.com/lists/oss-security/2021/01/15/1 (mailing-list, Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2020-14345?: CVE-2020-14345 is a high-severity vulnerability in X.org X Server, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 7.8/10. Published 2020-09-15.
How severe is CVE-2020-14345?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2020-14345 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.