Medium
Security advisory
A NULL pointer dereference issue was found in the ACPI code of QEMU. A malicious, privileged user within the guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-4158
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 09:25 UTC · Revision 1
Source evidence
A NULL pointer dereference issue was found in the ACPI code of QEMU. A malicious, privileged user within the guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition.
osv:CVE-2021-4158
Complete source record
{
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"url": "https://osv.dev/vulnerability/CVE-2021-4158",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-4158",
"summary": "A NULL pointer dereference issue was found in the ACPI code of QEMU. A malicious, privileged user within the guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition.",
"evidence": "osv:CVE-2021-4158",
"products": [],
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"metrics": [
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}
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"affected": [
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{
"range": [
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"source": "REFERENCES_COMMIT"
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"versions": [
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"database_specific": {
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"vanir_signatures": [
{
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"digest": {
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"source": "https://gitlab.com/qemu-project/qemu@9bd6565ccee68f72d5012e24646e12a1c662827e",
"target": {
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"source": "https://gitlab.com/qemu-project/qemu@9bd6565ccee68f72d5012e24646e12a1c662827e",
"target": {
"file": "hw/acpi/pcihp.c",
"function": "pci_write"
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"signature_type": "Function",
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"vanir_signatures_modified": "2026-10-24T14:21:20Z"
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"modified": "2026-10-24T14:21:20.031024562Z",
"provider": "osv",
"references": [
"https://access.redhat.com/security/cve/CVE-2021-4158",
"https://bugzilla.redhat.com/show_bug.cgi?id=2035002",
"https://gitlab.com/qemu-project/qemu/-/commit/9bd6565ccee68f72d5012e24646e12a1c662827e",
"https://www.mail-archive.com/qemu-devel%40nongnu.org/msg857944.html",
"https://gitlab.com/qemu-project/qemu/-/issues/770"
],
"provider_metadata": {
"unresolved_ranges": [
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],
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"extracted_events": [
{
"range": [
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},
{
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},
"related_cves": [
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"evidence": "/id"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 443633,
"published_at": "2022-08-24T16:15:09.66+00:00"
}