CVE-2018-20019

Name: CVE-2018-20019
Creator: NVD / NIST
Published: 2018-12-19T16:29:00.343+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 9.39%

Last modified Jun 17, 2026

CVE-2018-20019 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution. EPSS estimates a 9.39% chance of exploitation in the next 30 days.

Description

LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution

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

9.39%

94.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-787

Affected Software

Vendor	Product	Versions
Libvnc Project	Libvncserver	< 0.9.12
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	18.10
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Siemens	Simatic Itc1500 Firmware	>= 3.0.0.0, < 3.2.1.0
Siemens	Simatic Itc1500 Pro Firmware	>= 3.0.0.0, < 3.2.1.0
Siemens	Simatic Itc1900 Firmware	>= 3.0.0.0, < 3.2.1.0
Siemens	Simatic Itc1900 Pro Firmware	>= 3.0.0.0, < 3.2.1.0
Siemens	Simatic Itc2200 Firmware	>= 3.0.0.0, < 3.2.1.0
Siemens	Simatic Itc2200 Pro Firmware	>= 3.0.0.0, < 3.2.1.0

References

https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdfPatch, Third Party Advisory
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-029-libvnc-multiple-heap-out-of-bound-vulnerabilities/Broken Link
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.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/201908-05Third Party Advisory
https://usn.ubuntu.com/3877-1/Third Party Advisory
https://usn.ubuntu.com/4547-1/Third Party Advisory
https://usn.ubuntu.com/4587-1/Third Party Advisory
https://www.debian.org/security/2019/dsa-4383Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdfPatch, Third Party Advisory
https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-029-libvnc-multiple-heap-out-of-bound-vulnerabilities/Broken Link
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.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/201908-05Third Party Advisory
https://usn.ubuntu.com/3877-1/Third Party Advisory
https://usn.ubuntu.com/4547-1/Third Party Advisory
https://usn.ubuntu.com/4587-1/Third Party Advisory
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-2018-20019?

LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution

How severe is CVE-2018-20019?

CVE-2018-20019 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 9.39% probability of exploitation in the next 30 days.

How do I fix CVE-2018-20019?

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-2018-20019?

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

Scan your code now

Source: NVD / NIST