CVE-2018-20023

Name: CVE-2018-20023
Creator: NVD / NIST
Published: 2018-12-19T16:29:00.513+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 2.50%

Last modified Jun 17, 2026

CVE-2018-20023 is a vulnerability of currently unknown severity. LibVNC before 8b06f835e259652b0ff026898014fc7297ade858 contains CWE-665: Improper Initialization vulnerability in VNC Repeater client code that allows attacker to read stack memory and can be abuse for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and in bypassing ASLR. EPSS estimates a 2.50% chance of exploitation in the next 30 days.

Description

LibVNC before 8b06f835e259652b0ff026898014fc7297ade858 contains CWE-665: Improper Initialization vulnerability in VNC Repeater client code that allows attacker to read stack memory and can be abuse for information disclosure. Combined with another vulnerability, it can be used to leak stack memory layout and in bypassing ASLR

Metrics

EPSS Probability

2.50%

82.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-665

Affected Software

Vendor	Product	Versions
Libvnc Project	Libvncserver	< 0.9.12
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	18.10

References

https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-033-libvnc-memory-leak/Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/12/msg00017.htmlMailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html
https://security.gentoo.org/glsa/201908-05
https://usn.ubuntu.com/3877-1/Third Party Advisory
https://usn.ubuntu.com/4547-1/
https://usn.ubuntu.com/4587-1/
https://www.debian.org/security/2019/dsa-4383Third Party Advisory
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-033-libvnc-memory-leak/Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/12/msg00017.htmlMailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html
https://security.gentoo.org/glsa/201908-05
https://usn.ubuntu.com/3877-1/Third Party Advisory
https://usn.ubuntu.com/4547-1/
https://usn.ubuntu.com/4587-1/
https://www.debian.org/security/2019/dsa-4383Third Party Advisory

Timeline

Published: Dec 19, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-20023?

How severe is CVE-2018-20023?

Severity scoring for CVE-2018-20023 is pending analysis. The EPSS model estimates a 2.50% probability of exploitation in the next 30 days.

How do I fix CVE-2018-20023?

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-2018-20023?

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

Scan your code now

Source: NVD / NIST