CVE-2019-20788

CRITICALNVD 9.89.8—

9.8

libvncclient/cursor.c in LibVNCServer through 0.9.12 has a HandleCursorShape integer overflow and heap-based buffer overflow via a large height or width value. NOTE: this may overlap CVE-2019-15690.

CVSS v3: 9.8
EG Score: 9.8(medium)
EPSS: 74.3%
KEV: Not listed

Published

April 23, 2020

Last Modified

November 21, 2024

Advisory Details (2)

Auto-updated May 27, 2026

Patch available. Sources: github_commit, github.

github Patch Available

GHSL-2020-064: integer overflow in LibVNCClient HandleCursorShape resulting in remote heap overflow - CVE-2019-20788 | GitHub Security Lab

https://securitylab.github.com/advisories/GHSL-2020-064-libvnc-libvncclient

github_commit Patch Available

commit 54220248886b (LibVNC/libvncserver)

Patch available: LibVNC/libvncserver LibVNCServer-0.9.13 (contains commit 54220248886b)

https://github.com/LibVNC/libvncserver/commit/54220248886b5001fbbb9fa73c4e1a2cb9413fed

Patch Availability(4)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	libvncserver1 (0.9.10+dfsg-3ubuntu0.16.04.4) @ xenial	2026-05-27	ubuntu
redhat	libvncserver-0:0.9.9-14.el7_7	2020-03-23	redhat
redhat	libvncserver-0:0.9.11-9.el8_1.2	2020-03-23	redhat
redhat	libvncserver-0:0.9.11-9.el8_0.2	2020-03-23	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(4)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 9× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-04 13:10 UTCepss_batch
2026-06-04 13:10 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 00:14 UTCepss_batch
2026-05-31 00:14 UTCepss_batch
2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:38 UTCepss_batch
2026-05-27 04:20 UTCEG score recompute
2026-05-27 04:20 UTCVendor advisory
2026-05-27 04:20 UTCGHSA enrichment
2026-05-26 13:42 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 03:16 UTCOSV refresh

Frequently asked(5)

What is CVE-2019-20788?

CVE-2019-20788 is a critical vulnerability published on April 23, 2020. libvncclient/cursor.c in LibVNCServer through 0.9.12 has a HandleCursorShape integer overflow and heap-based buffer overflow via a large height or width value. NOTE: this may overlap CVE-2019-15690.

When was CVE-2019-20788 disclosed?

CVE-2019-20788 was first published in the National Vulnerability Database on April 23, 2020, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2019-20788 actively exploited?

CVE-2019-20788 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 74.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2019-20788?

CVE-2019-20788 has a CVSS v3 base score of 9.8 (NVD).

How do I remediate CVE-2019-20788?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-20788, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2019-20788

Published

Last Modified

Advisory Details (2)

GHSL-2020-064: integer overflow in LibVNCClient HandleCursorShape resulting in remote heap overflow - CVE-2019-20788 | GitHub Security Lab

commit 54220248886b (LibVNC/libvncserver)

Patch Availability(4)

Weakness Classification(2)

All Vendor Advisories

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2019-20788?

Same vendor

Same CWE

CVE-2019-20788

📅 Published

🔄 Last Modified

📋 Advisory Details (2)

GHSL-2020-064: integer overflow in LibVNCClient HandleCursorShape resulting in remote heap overflow - CVE-2019-20788 | GitHub Security Lab

commit 54220248886b (LibVNC/libvncserver)

Patch Availability(4)

Weakness Classification(2)

All Vendor Advisories

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2019-20788?

🔗 Related CVEs(same vendor + same CWE)

Same vendor

Same CWE

Published

Last Modified

Advisory Details (2)

Frequently asked(5)

Related CVEs(same vendor + same CWE)