Medium
Security advisory
An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU. This flaw occurs in the ati_2d_blt() routine while handling MMIO write operations when the guest provides invalid values for the destination display parameters. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-3638
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 05:43 UTC · Revision 1
Source evidence
An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU. This flaw occurs in the ati_2d_blt() routine while handling MMIO write operations when the guest provides invalid values for the destination display parameters. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.
osv:CVE-2021-3638
Complete source record
{
"id": "9900048482077355485d36aa0b128d436461b3788fd1b4e561eefa8aa4689a84",
"url": "https://osv.dev/vulnerability/CVE-2021-3638",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-3638",
"summary": "An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU. This flaw occurs in the ati_2d_blt() routine while handling MMIO write operations when the guest provides invalid values for the destination display parameters. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.",
"evidence": "osv:CVE-2021-3638",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2021-3638",
"aliases": [
"CVE-2021-3638"
],
"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": [
{
"ranges": [
{
"repo": "https://github.com/qemu/qemu",
"type": "GIT",
"events": [
{
"introduced": "131b9a05705636086699df15d4a6d328bb2585e8"
},
{
"last_affected": "f9baca549e44791be0dd98de15add3d8452a8af0"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.0.0"
},
{
"last_affected": "6.1.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v6.1.0",
"v6.0.0",
"v6.1.0-rc4",
"v6.1.0-rc3",
"v6.1.0-rc2",
"v6.1.0-rc1",
"v6.1.0-rc0",
"v6.0.0-rc5",
"v6.0.0-rc4",
"v6.0.0-rc3",
"v6.0.0-rc2",
"v6.0.0-rc1",
"v6.0.0-rc0",
"v5.2.0",
"v5.2.0-rc4",
"v5.2.0-rc3",
"v5.2.0-rc2",
"v5.2.0-rc1",
"v5.2.0-rc0",
"v5.0.0",
"v5.1.0",
"v5.1.0-rc3",
"v5.1.0-rc2",
"v5.1.0-rc1",
"v5.1.0-rc0",
"v4.2.0",
"v5.0.0-rc4",
"v5.0.0-rc3",
"v5.0.0-rc2",
"v5.0.0-rc1",
"v5.0.0-rc0",
"v4.2.0-rc5",
"v4.2.0-rc4",
"v4.2.0-rc3",
"v4.2.0-rc2",
"v4.2.0-rc1",
"v4.2.0-rc0",
"v4.1.0",
"v4.0.0",
"v4.1.0-rc5",
"v4.1.0-rc4",
"v4.1.0-rc3",
"v4.1.0-rc2",
"v4.1.0-rc1",
"v4.1.0-rc0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-3638.json"
}
},
{
"ranges": [
{
"repo": "https://gitlab.com/qemu-project/qemu",
"type": "GIT",
"events": [
{
"introduced": "131b9a05705636086699df15d4a6d328bb2585e8"
},
{
"last_affected": "f9baca549e44791be0dd98de15add3d8452a8af0"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "4.0.0"
},
{
"last_affected": "6.1.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v6.1.0",
"v6.0.0",
"v6.1.0-rc4",
"v6.1.0-rc3",
"v6.1.0-rc2",
"v6.1.0-rc1",
"v6.1.0-rc0",
"v6.0.0-rc5",
"v6.0.0-rc4",
"v6.0.0-rc3",
"v6.0.0-rc2",
"v6.0.0-rc1",
"v6.0.0-rc0",
"v5.2.0",
"v5.2.0-rc4",
"v5.2.0-rc3",
"v5.2.0-rc2",
"v5.2.0-rc1",
"v5.2.0-rc0",
"v5.0.0",
"v5.1.0",
"v5.1.0-rc3",
"v5.1.0-rc2",
"v5.1.0-rc1",
"v5.1.0-rc0",
"v4.2.0",
"v5.0.0-rc4",
"v5.0.0-rc3",
"v5.0.0-rc2",
"v5.0.0-rc1",
"v5.0.0-rc0",
"v4.2.0-rc5",
"v4.2.0-rc4",
"v4.2.0-rc3",
"v4.2.0-rc2",
"v4.2.0-rc1",
"v4.2.0-rc0",
"v4.1.0",
"v4.0.0",
"v4.1.0-rc5",
"v4.1.0-rc4",
"v4.1.0-rc3",
"v4.1.0-rc2",
"v4.1.0-rc1",
"v4.1.0-rc0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-3638.json"
}
}
],
"modified": "2026-10-24T10:30:32.898968267Z",
"provider": "osv",
"references": [
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GTVPHLLXJ65BUMFBUUZ35F3J632SLFRK/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7J5IRXJYLELW7D43A75LOWRUE5EU54O/",
"https://security.netapp.com/advisory/ntap-20220407-0003/",
"https://ubuntu.com/security/CVE-2021-3638",
"https://bugzilla.redhat.com/show_bug.cgi?id=1979858",
"https://lists.nongnu.org/archive/html/qemu-devel/2021-09/msg01682.html"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "36"
},
{
"last_affected": "36"
},
{
"introduced": "37"
},
{
"last_affected": "37"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-3638",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 433130,
"published_at": "2022-03-03T23:15:08.147+00:00"
}