CVE catalog

CVE-2019-20788

libvncserver affected and fixed versions

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.

Severity: Critical · CVSS 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Published: Nov 17, 2019, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 2.50% · Oct 27, 2026

Projects and upstream resources

[libvncserver][Source-reported homepage]

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Distribution / release	Package	Version	Status	Source
Debiantrixie	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debiantrixie	libvncserver	`0.9.15+dfsg-1+deb13u2`	Fixed	[CVE-2019-20788]
Debiansid	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debiansid	libvncserver	`0.9.15+dfsg-6`	Fixed	[CVE-2019-20788]
Debianforky	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debianforky	libvncserver	`0.9.15+dfsg-6`	Fixed	[CVE-2019-20788]
Debianbookworm	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debianbookworm	libvncserver	`0.9.14+dfsg-1+deb12u2`	Fixed	[CVE-2019-20788]

Showing 8 fix observations. All 20 observations, including unknown and conflicting reports, are available below.

Provider details and historical evidence

Distribution / release	Package	Version	Status	Source
UnknownRelease not reported	libvncserver	`0.9.12+dfsg-9`	UnknownSource applicability is not established	Provider not reported
Debianbookworm	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debianbookworm	libvncserver	`0.9.14+dfsg-1+deb12u2`	Fixed	[CVE-2019-20788]
Debianforky	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debianforky	libvncserver	`0.9.15+dfsg-6`	Fixed	[CVE-2019-20788]
Debiansid	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debiansid	libvncserver	`0.9.15+dfsg-6`	Fixed	[CVE-2019-20788]
Debiantrixie	libvncserver	`0.9.12+dfsg-9`	FixedDistribution-reported fixed boundary	[CVE-2019-20788]
Debiantrixie	libvncserver	`0.9.15+dfsg-1+deb13u2`	Fixed	[CVE-2019-20788]
Ubuntu14.04	x11vnc	`0.9.13-1.1`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu16.04	libvncserver	`0.9.10+dfsg-3`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu16.04	libvncserver	`0.9.10+dfsg-3build1`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu16.04	libvncserver	`0.9.10+dfsg-3ubuntu0.16.04.1`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu16.04	libvncserver	`0.9.10+dfsg-3ubuntu0.16.04.2`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu16.04	libvncserver	`0.9.10+dfsg-3ubuntu0.16.04.3`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu16.04	libvncserver	`0.9.10+dfsg-3ubuntu0.16.04.4`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu18.04	libvncserver	`0.9.11+dfsg-1`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu18.04	libvncserver	`0.9.11+dfsg-1ubuntu1`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu18.04	libvncserver	`0.9.11+dfsg-1ubuntu1.1`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC
Ubuntu18.04	libvncserver	`0.9.11+dfsg-1ubuntu1.2`	UnknownSource applicability is not established	[UBUNTU-CVE-2019-20788]Apr 22, 2026, 12:16:45 PM UTC

Original provider fields

{
  "package_releases": [
    {
      "name": "libvncserver",
      "status": "fixed",
      "release": "sid",
      "version": "0.9.15+dfsg-6"
    },
    {
      "name": "libvncserver",
      "status": "fixed",
      "release": "forky",
      "version": "0.9.15+dfsg-6"
    },
    {
      "name": "libvncserver",
      "status": "fixed",
      "release": "trixie",
      "version": "0.9.15+dfsg-1+deb13u2"
    },
    {
      "name": "libvncserver",
      "status": "fixed",
      "release": "bookworm",
      "version": "0.9.14+dfsg-1+deb12u2"
    }
  ],
  "fixed_versions": [
    {
      "bug": 954163,
      "name": "libvncserver",
      "type": "source",
      "origin": null,
      "release": "sid",
      "urgency": "not yet assigned",
      "fixed_version": "0.9.12+dfsg-9"
    },
    {
      "bug": 954163,
      "name": "libvncserver",
      "type": "source",
      "origin": null,
      "release": "forky",
      "urgency": "not yet assigned",
      "fixed_version": "0.9.12+dfsg-9"
    },
    {
      "bug": 954163,
      "name": "libvncserver",
      "type": "source",
      "origin": null,
      "release": "trixie",
      "urgency": "not yet assigned",
      "fixed_version": "0.9.12+dfsg-9"
    },
    {
      "bug": 954163,
      "name": "libvncserver",
      "type": "source",
      "origin": null,
      "release": "bookworm",
      "urgency": "not yet assigned",
      "fixed_version": "0.9.12+dfsg-9"
    }
  ],
  "distribution_packages": [
    {
      "name": "libvncserver",
      "fixed_version": "0.9.12+dfsg-9",
      "applicability_unknown": true
    },
    {
      "name": "x11vnc",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "14.04",
      "versions": [
        "0.9.13-1.1"
      ],
      "ecosystem": "deb",
      "provider_url": "https://osv.dev/vulnerability/UBUNTU-CVE-2019-20788",
      "fixed_version": "",
      "provider_source": "pypi",
      "provider_record_id": "UBUNTU-CVE-2019-20788",
      "provider_updated_at": "2026-04-22T12:16:45.789148Z",
      "applicability_unknown": true
    },
    {
      "name": "libvncserver",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.9.10+dfsg-3ubuntu0.16.04.4"
            }
          ]
        }
      ],
      "release": "16.04",
      "versions": [
        "0.9.10+dfsg-3",
        "0.9.10+dfsg-3build1",
        "0.9.10+dfsg-3ubuntu0.16.04.1",
        "0.9.10+dfsg-3ubuntu0.16.04.2",
        "0.9.10+dfsg-3ubuntu0.16.04.3"
      ],
      "ecosystem": "deb",
      "provider_url": "https://osv.dev/vulnerability/UBUNTU-CVE-2019-20788",
      "fixed_version": "0.9.10+dfsg-3ubuntu0.16.04.4",
      "provider_source": "pypi",
      "provider_record_id": "UBUNTU-CVE-2019-20788",
      "provider_updated_at": "2026-04-22T12:16:45.789148Z",
      "applicability_unknown": true
    },
    {
      "name": "libvncserver",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.9.11+dfsg-1ubuntu1.2"
            }
          ]
        }
      ],
      "release": "18.04",
      "versions": [
        "0.9.11+dfsg-1",
        "0.9.11+dfsg-1ubuntu1",
        "0.9.11+dfsg-1ubuntu1.1"
      ],
      "ecosystem": "deb",
      "provider_url": "https://osv.dev/vulnerability/UBUNTU-CVE-2019-20788",
      "fixed_version": "0.9.11+dfsg-1ubuntu1.2",
      "provider_source": "pypi",
      "provider_record_id": "UBUNTU-CVE-2019-20788",
      "provider_updated_at": "2026-04-22T12:16:45.789148Z",
      "applicability_unknown": true
    }
  ]
}

[Debian bug #954163]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[libvncclient1]Unknown
Source package: [libvncserver]
Details (2)
- 0.9.14+dfsg-1+deb12u2 · amd64 · bookworm
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
- 0.9.14+dfsg-1+deb12u2 · arm64 · bookworm
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
[libvncserver1]Unknown
Source package: [libvncserver]
Details (2)
- 0.9.14+dfsg-1+deb12u2 · amd64 · bookworm
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
- 0.9.14+dfsg-1+deb12u2 · arm64 · bookworm
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
[libvncserver-dev]Unknown
Source package: [libvncserver]
Details (2)
- 0.9.14+dfsg-1+deb12u2 · amd64 · bookworm
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12
- 0.9.14+dfsg-1+deb12u2 · arm64 · bookworm
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · bookworm; dsa · libvncserver · debian · 12

[Debian 13 (Trixie)]

[libvncclient1]Unknown
Source package: [libvncserver]
Details (2)
- 0.9.15+dfsg-1+deb13u2 · amd64 · trixie
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · 13
- 0.9.15+dfsg-1+deb13u2 · arm64 · trixie
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · 13
[libvncserver1]Unknown
Source package: [libvncserver]
Details (2)
- 0.9.15+dfsg-1+deb13u2 · amd64 · trixie
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · 13
- 0.9.15+dfsg-1+deb13u2 · arm64 · trixie
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · 13
[libvncserver-dev]Unknown
Source package: [libvncserver]
Details (2)
- 0.9.15+dfsg-1+deb13u2 · amd64 · trixie
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · 13
- 0.9.15+dfsg-1+deb13u2 · arm64 · trixie
  Fixed · Fixed: 0.9.12+dfsg-9
  dsa · libvncserver · debian · 13

Observed: Oct 23, 2026, 5:43:50 PM UTC

References

[CISA cybersecurity advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]