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No exploitation reportedFix available

CVE-2019-20788

No exploitation reported by the sources we read.

  • Published2020-04-23
  • WeaknessCWE-190 · CWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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.

Timeline

dates in UTC
  1. 2020-04-2319:15CVE publishedNVD

Versions per branch

NVD
Canonical ubuntu linux
BranchAffectedFixed in
14.4= 14.04no fix published
16.4= 16.04no fix published
18.4= 18.04no fix published
18.10= 18.10no fix published
Debian debian linux
BranchAffectedFixed in
8.0= 8.0no fix published
9.0= 9.0no fix published
Libvnc project libvncserver
BranchAffectedFixed in
0.9≤ 0.9.12no fix published

6 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • libvncserverUbuntu:20.04:LTSall versions · fixed in 0.9.12+dfsg-9ubuntu0.1
  • libvncserverUbuntu:18.04:LTSall versions · fixed in 0.9.11+dfsg-1ubuntu1.2
  • libvncserverUbuntu:16.04:LTSall versions · fixed in 0.9.10+dfsg-3ubuntu0.16.04.4
  • libvncserverRed Hat:rhel_e4s:8.0::appstreamall versions · fixed in 0:0.9.11-9.el8_0.2and 2 other packages
  • libvncserverRed Hat:enterprise_linux:8::crball versions · fixed in 0:0.9.11-9.el8_1.2and 3 other packages
  • libvncserverRed Hat:enterprise_linux:8::appstreamall versions · fixed in 0:0.9.11-9.el8_1.2and 2 other packages
  • libvncserverRed Hat:enterprise_linux:7::workstationall versions · fixed in 0:0.9.9-14.el7_7and 2 other packages
  • libvncserverRed Hat:enterprise_linux:7::serverall versions · fixed in 0:0.9.9-14.el7_7and 2 other packages

31 more package ranges on OSV.dev

Vendor advisories

  • CVE-2019-20788 Red Hat Product Security69 products fixed

    libvncserver: integer overflow and heap-based buffer overflow in libvncclient/cursor.c in HandleCursorShape function

  • ICSA-21-350-12 CISA6 known affected

    Siemens SIMATIC ITC

    SIMATIC ITC1500 V3 · SIMATIC ITC1500 V3 PRO · SIMATIC ITC1900 V3 · +3 more

  • SSA-390195 Siemens ProductCERT6 known affected

    SSA-390195: LibVNC Vulnerabilities in SIMATIC ITC Products

    SIMATIC ITC1500 V3 · SIMATIC ITC1500 V3 PRO · SIMATIC ITC1900 V3 · +3 more

  • RHSA-2020:0913 Red Hat Product Security31 products fixed

    Red Hat Security Advisory: libvncserver security update

  • RHSA-2020:0920 Red Hat Product Security28 products fixed

    Red Hat Security Advisory: libvncserver security update

  • RHSA-2020:0921 Red Hat Product Security10 products fixed

    Red Hat Security Advisory: libvncserver security update

Full record on NVD

Fix

  1. Vendor fix Siemens ProductCERT SSA-390195 · 6 productsUpdate to V3.2.1.0 or later version
  2. Vendor fix CISA ICSA-21-350-12 · 6 productsUpdate to V3.2.1.0 or later version
  3. Vendor fix Red Hat Product Security RHSA-2020:0913 · 31 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
  4. Mitigation from the vendor Siemens ProductCERT SSA-390195 · 6 productsMonitor and restrict access to port 5900/tcp to trusted IP addresses only
  5. Mitigation from the vendor CISA ICSA-21-350-12 · 6 productsMonitor and restrict access to port 5900/tcp to trusted IP addresses only

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2020-04-23
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-7397-jpw5-q274

Frequently asked questions

What is CVE-2019-20788?

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.

Is CVE-2019-20788 actively exploited?

Active exploitation of CVE-2019-20788 has not been confirmed. Its EPSS score was 2.5% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

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

CVE-2019-20788 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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