Medium
Security advisory
Quick emulator (Qemu) built with the Cirrus CLGD 54xx VGA Emulator support is vulnerable to a divide by zero issue. It could occur while copying VGA data when cirrus graphics mode was set to be VGA. A privileged user inside guest could use this flaw to crash the Qemu process instance on the host, resulting in DoS.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2016-9921
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 04:20 UTC · Revision 1
Source evidence
Quick emulator (Qemu) built with the Cirrus CLGD 54xx VGA Emulator support is vulnerable to a divide by zero issue. It could occur while copying VGA data when cirrus graphics mode was set to be VGA. A privileged user inside guest could use this flaw to crash the Qemu process instance on the host, resulting in DoS.
osv:CVE-2016-9921
Complete source record
{
"id": "73c68765fcbf672d3a6dcb9ebfd6adea798fce65513eeb76733c5325757e1534",
"url": "https://osv.dev/vulnerability/CVE-2016-9921",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2016-9921",
"summary": "Quick emulator (Qemu) built with the Cirrus CLGD 54xx VGA Emulator support is vulnerable to a divide by zero issue. It could occur while copying VGA data when cirrus graphics mode was set to be VGA. A privileged user inside guest could use this flaw to crash the Qemu process instance on the host, resulting in DoS.",
"evidence": "osv:CVE-2016-9921",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2016-9921",
"aliases": [
"CVE-2016-9921"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H"
}
],
"affected": [
{
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{
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},
{
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{
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{
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}
},
{
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"database_specific": {
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{
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{
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{
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}
}
],
"modified": "2026-10-24T10:30:17.354736551Z",
"provider": "osv",
"references": [
"https://access.redhat.com/errata/RHSA-2017:2392",
"https://access.redhat.com/errata/RHSA-2017:2408",
"https://lists.debian.org/debian-lts-announce/2018/09/msg00007.html",
"https://security.gentoo.org/glsa/201701-49"
],
"provider_metadata": {
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{
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}
},
"related_cves": [
{
"value": "CVE-2016-9921",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 429546,
"published_at": "2016-12-23T22:59:00.55+00:00"
}