What is CVE-2018-20123?

CVE-2018-20123 is a medium-severity vulnerability in Qemu, classified under Missing Release of Resource after Effective Lifetime. CVSS score: 5.5/10. Published 2018-12-17.

How severe is CVE-2018-20123?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Vulnerability in Qemu

CVE-2018-20123

pvrdma_realize in hw/rdma/vmw/pvrdma_main.c in QEMU has a Memory leak after an initialisation error.

Published 2018-12-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (39.6th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Qemu
Canonical Ubuntu Linux — versions 14.04, 16.04, 18.04
Fedoraproject Fedora — versions 30

Weakness classification (CWE)

CWE-772 — Missing Release of Resource after Effective Lifetime

References

www.securityfocus.com/bid/106219 (VDB Entry, Third Party Advisory, vdb-entry)
www.openwall.com/lists/oss-security/2018/12/13/4 (mailing-list, Patch, Mailing List, Third Party Advisory)
lists.gnu.org/archive/html/qemu-devel/2018-12/msg02817.html (mailing-list, Patch, Mailing List, Third Party Advisory)
usn.ubuntu.com/3923-1/ (vendor-advisory, Third Party Advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)

Frequently asked questions

What is CVE-2018-20123?: CVE-2018-20123 is a medium-severity vulnerability in Qemu, classified under Missing Release of Resource after Effective Lifetime. CVSS score: 5.5/10. Published 2018-12-17.
How severe is CVE-2018-20123?: Medium severity. CVSS v3 base score is 5.5 out of 10.