How severe is CVE-2020-14398?

CVE-2020-14398 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-14398 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-14398?

CVE-2020-14398 primarily affects Libvnc Project Libvncserver. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-14398?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-14398 published?

CVE-2020-14398 was published on 2020-06-17 and last updated on 2026-06-17.

CVE-2020-14398

CVE-2020-14398 is a high-severity vulnerability in Libvnc Project Libvncserver with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Libvnc Project Libvncserver
Published: 2020-06-17
Last modified: 2026-06-17

Description

An issue was discovered in LibVNCServer before 0.9.13. An improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c.

Frequently asked questions

What is CVE-2020-14398?: An issue was discovered in LibVNCServer before 0.9.13. An improperly closed TCP connection causes an infinite loop in libvncclient/sockets.c.
How severe is CVE-2020-14398?: CVE-2020-14398 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-14398 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-14398?: CVE-2020-14398 primarily affects Libvnc Project Libvncserver. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-14398?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-14398 published?: CVE-2020-14398 was published on 2020-06-17 and last updated on 2026-06-17.

References

Affected products (16)

cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1500_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc1900_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc2200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itc2200_pro_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

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