What’s Vulnerable › Vulnerabilities
CVE-2018-20019
- Severity: critical (CVSS 9.8 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 9.6% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2018-12-19 · updated 2026-06-17
- Weakness: CWE-787
Description
LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution
Affected products
- Canonical Ubuntu Linux: 14.04, 16.04, 18.04, 18.10
- Debian Linux: 8.0, 9.0
- Libvnc Project Libvncserver: before 0.9.12 — fixed in 0.9.12
- Siemens Simatic Itc1500 Firmware: from 3.0.0.0 before 3.2.1.0 — fixed in 3.2.1.0
- Siemens Simatic Itc1500 Pro Firmware: from 3.0.0.0 before 3.2.1.0 — fixed in 3.2.1.0
- Siemens Simatic Itc1900 Firmware: from 3.0.0.0 before 3.2.1.0 — fixed in 3.2.1.0
- Siemens Simatic Itc1900 Pro Firmware: from 3.0.0.0 before 3.2.1.0 — fixed in 3.2.1.0
- Siemens Simatic Itc2200 Firmware: from 3.0.0.0 before 3.2.1.0 — fixed in 3.2.1.0
- Siemens Simatic Itc2200 Pro Firmware: from 3.0.0.0 before 3.2.1.0 — fixed in 3.2.1.0
How to fix
Upgrade to a fixed version: Libvnc Project Libvncserver 0.9.12; Siemens Simatic Itc1500 Firmware 3.2.1.0; Siemens Simatic Itc1500 Pro Firmware 3.2.1.0; Siemens Simatic Itc1900 Firmware 3.2.1.0; Siemens Simatic Itc1900 Pro Firmware 3.2.1.0; Siemens Simatic Itc2200 Firmware 3.2.1.0; Siemens Simatic Itc2200 Pro Firmware 3.2.1.0. Check the vendor advisory for mitigations.
References
- https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-029-libvnc-multiple-heap-out-of-bound-vulnerabilities/
- https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html
- https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html
- https://security.gentoo.org/glsa/201908-05
- https://usn.ubuntu.com/3877-1/
- https://usn.ubuntu.com/4547-1/
- https://usn.ubuntu.com/4587-1/
- https://www.debian.org/security/2019/dsa-4383
- https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-029-libvnc-multiple-heap-out-of-bound-vulnerabilities/
- https://lists.debian.org/debian-lts-announce/2018/12/msg00017.html
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