CVE-2020-14396

An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.

Published: 2020-06-17 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-14396 is rated Moderate Risk (58.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.58%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-14396

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-12-28 1.07% 1.58% +0.51%
2 2025-12-27 1.58% 1.07% -0.51%
3 2025-10-28 — 1.58% —

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-14396

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2020-14396

OS Trackers for CVE-2020-14396

vendor priority summary link
alpine high CVE-2020-14396: 1 source package rows (libvncserver); 8 state rows across 4 repos (3.10-main, 3.11-main, 3.22-community, edge-community); fixed 0, open 8. https://security.alpinelinux.org/vuln/CVE-2020-14396
debian not yet assigned CVE-2020-14396 not yet assigned priority: Debian including 1 source packages (libvncserver), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-14396
redhat medium — https://access.redhat.com/security/cve/CVE-2020-14396
suse medium CVE-2020-14396 severity moderate: SUSE including 4 source package names (LibVNCServer, LibVNCServer-devel, libvncclient0, libvncserver0), 43 product×package rows across 20 product lines (SUSE Linux Enterprise High Performance Computing 12 SP4, SUSE Linux Enterprise High Performance Computing 12 SP5, … (20 product lines)): Known Not Affected 43. https://www.suse.com/security/cve/CVE-2020-14396/
ubuntu medium CVE-2020-14396 medium priority: Ubuntu including 3 source packages (libvncserver, veyon, x11vnc), 51 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 23, ignored 16, needs-triage 7, DNE 4, released 1. https://ubuntu.com/security/CVE-2020-14396

Affected software / configurations for CVE-2020-14396

Vendor Product Version Raw CPE
libvnc_project libvncserver <= 0.9.12 cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:*
canonical ubuntu_linux 14.04 cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
canonical ubuntu_linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 18.04 cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 18.10 cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
canonical ubuntu_linux 20.04 cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
siemens simatic_itc1500_firmware >= 3.0.0.0, < 3.2.1.0 cpe:2.3:o:siemens:simatic_itc1500_firmware:*:*:*:*:*:*:*:*
siemens simatic_itc1500_pro_firmware >= 3.0.0.0, < 3.2.1.0 cpe:2.3:o:siemens:simatic_itc1500_pro_firmware:*:*:*:*:*:*:*:*
siemens simatic_itc1900_firmware >= 3.0.0.0, < 3.2.1.0 cpe:2.3:o:siemens:simatic_itc1900_firmware:*:*:*:*:*:*:*:*
siemens simatic_itc1900_pro_firmware >= 3.0.0.0, < 3.2.1.0 cpe:2.3:o:siemens:simatic_itc1900_pro_firmware:*:*:*:*:*:*:*:*
siemens simatic_itc2200_firmware >= 3.0.0.0, < 3.2.1.0 cpe:2.3:o:siemens:simatic_itc2200_firmware:*:*:*:*:*:*:*:*
siemens simatic_itc2200_pro_firmware >= 3.0.0.0, < 3.2.1.0 cpe:2.3:o:siemens:simatic_itc2200_pro_firmware:*:*:*:*:*:*:*:*

References for CVE-2020-14396

cvelogic Threat Intelligence