Critical
Security advisory
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2019-20788
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:29 UTC · Revision 1
Source evidence
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.
osv:CVE-2019-20788
Complete source record
{
"id": "a499077cafb23e8df5a1a7348a26afb361dee4d7ac6145c383bcdbe4027e94bf",
"url": "https://osv.dev/vulnerability/CVE-2019-20788",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2019-20788",
"summary": "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.",
"evidence": "osv:CVE-2019-20788",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2019-20788",
"aliases": [
"CVE-2019-20788"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/libvnc/libvncserver",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "0a70095271d845d16a3ed17354841b01f33963ad"
},
{
"fixed": "54220248886b5001fbbb9fa73c4e1a2cb9413fed"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "0.9.12"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "54220248886b5001fbbb9fa73c4e1a2cb9413fed"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"LibVNCServer-0.9.12",
"LibVNCServer-0.9.11",
"LibVNCServer-0.9.10",
"LibVNCServer-0.9.9",
"LibVNCServer-0.9.8",
"X11VNC_0_9_12",
"X11VNC_0_9_11",
"X11VNC_0_9_10",
"X11VNC_0_9_9",
"X11VNC_0_9_8",
"X11VNC_0_9_7",
"X11VNC_REL_0_9_6",
"X11VNC_REL_0_9_5",
"X11VNC_REL_0_9_4"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-20788.json",
"vanir_signatures": [
{
"id": "CVE-2019-20788-189abd97",
"digest": {
"length": 2878,
"function_hash": "166509097659370788785687778228924176187"
},
"source": "https://github.com/libvnc/libvncserver/commit/54220248886b5001fbbb9fa73c4e1a2cb9413fed",
"target": {
"file": "libvncclient/cursor.c",
"function": "HandleCursorShape"
},
"deprecated": false,
"signature_type": "Function",
"signature_version": "v1"
},
{
"id": "CVE-2019-20788-36246abd",
"digest": {
"threshold": 0.9,
"line_hashes": [
"102057262279662452688778988803141241357",
"175955773102106351237323041340518821685",
"240545567691954465949188256110399956644",
"204796747639085440341262894639991613085"
]
},
"source": "https://github.com/libvnc/libvncserver/commit/54220248886b5001fbbb9fa73c4e1a2cb9413fed",
"target": {
"file": "libvncclient/cursor.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-20T13:42:59Z"
}
}
],
"modified": "2026-10-20T13:42:59.839325709Z",
"provider": "osv",
"references": [
"https://usn.ubuntu.com/4407-1/",
"https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf",
"https://github.com/LibVNC/libvncserver/commit/54220248886b5001fbbb9fa73c4e1a2cb9413fed",
"https://securitylab.github.com/advisories/GHSL-2020-064-libvnc-libvncclient"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:siemens:simatic_itc1500_firmware:*:*:*:*:*:*:*:*"
],
"vendor_product": "siemens:simatic_itc1500_firmware",
"extracted_events": [
{
"range": [
{
"introduced": "3.0.0.0"
},
{
"fixed": "3.2.1.0"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:siemens:simatic_itc1500_pro_firmware:*:*:*:*:*:*:*:*"
],
"vendor_product": "siemens:simatic_itc1500_pro_firmware",
"extracted_events": [
{
"range": [
{
"introduced": "3.0.0.0"
},
{
"fixed": "3.2.1.0"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:siemens:simatic_itc1900_firmware:*:*:*:*:*:*:*:*"
],
"vendor_product": "siemens:simatic_itc1900_firmware",
"extracted_events": [
{
"range": [
{
"introduced": "3.0.0.0"
},
{
"fixed": "3.2.1.0"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:siemens:simatic_itc1900_pro_firmware:*:*:*:*:*:*:*:*"
],
"vendor_product": "siemens:simatic_itc1900_pro_firmware",
"extracted_events": [
{
"range": [
{
"introduced": "3.0.0.0"
},
{
"fixed": "3.2.1.0"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:siemens:simatic_itc2200_firmware:*:*:*:*:*:*:*:*"
],
"vendor_product": "siemens:simatic_itc2200_firmware",
"extracted_events": [
{
"range": [
{
"introduced": "3.0.0.0"
},
{
"fixed": "3.2.1.0"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:siemens:simatic_itc2200_pro_firmware:*:*:*:*:*:*:*:*"
],
"vendor_product": "siemens:simatic_itc2200_pro_firmware",
"extracted_events": [
{
"range": [
{
"introduced": "3.0.0.0"
},
{
"fixed": "3.2.1.0"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"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:*:*:*:*:*:*:*"
],
"vendor_product": "canonical:ubuntu_linux",
"extracted_events": [
{
"range": [
{
"introduced": "14.04"
},
{
"last_affected": "14.04"
},
{
"introduced": "16.04"
},
{
"last_affected": "16.04"
},
{
"introduced": "16.04"
},
{
"last_affected": "16.04"
},
{
"introduced": "18.04"
},
{
"last_affected": "18.04"
},
{
"introduced": "18.10"
},
{
"last_affected": "18.10"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*",
"cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "8.0"
},
{
"last_affected": "8.0"
},
{
"introduced": "9.0"
},
{
"last_affected": "9.0"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2019-20788",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 387982,
"published_at": "2020-04-23T19:15:12.763+00:00"
}