linux — security advisory
A use-after-free in function hci_sock_bound_ioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hci_unregister_dev() together with one of the calls hci_sock_blacklist_add(), hci_sock_blacklist_del(), hci_get_conn_info(), hci_get_auth_info(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system. This flaw affects the Linux kernel versions prior to 5.13-rc5.
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 5.10.46-1
- CVEs
- CVE-2021-3573
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:36 UTC · Revision 1
Source evidence
A use-after-free in function hci_sock_bound_ioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hci_unregister_dev() together with one of the calls hci_sock_blacklist_add(), hci_sock_blacklist_del(), hci_get_conn_info(), hci_get_auth_info(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system. This flaw affects the Linux kernel versions prior to 5.13-rc5.
osv:DEBIAN-CVE-2021-3573
linux
Fixed versions: 5.10.46-1
linux
Fixed versions: 5.10.46-1
linux
Fixed versions: 5.10.46-1
Complete source record
{
"id": "fcb0605528753b576f9ae1a8070aae32198a61e87969235c2d58d2a0bcd3289d",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-3573",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-3573",
"summary": "A use-after-free in function hci_sock_bound_ioctl() of the Linux kernel HCI subsystem was found in the way user calls ioct HCIUNBLOCKADDR or other way triggers race condition of the call hci_unregister_dev() together with one of the calls hci_sock_blacklist_add(), hci_sock_blacklist_del(), hci_get_conn_info(), hci_get_auth_info(). A privileged local user could use this flaw to crash the system or escalate their privileges on the system. This flaw affects the Linux kernel versions prior to 5.13-rc5.",
"evidence": "osv:DEBIAN-CVE-2021-3573",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
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"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
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"affected_versions": []
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],
"severity": "medium",
"structured": {
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"aliases": [
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"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H"
}
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"affected": [
{
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"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-3573.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
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],
"package": {
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"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-3573.json"
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"ecosystem_specific": {
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{
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],
"package": {
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"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2021-3573.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:29.163054059Z",
"provider": "osv",
"upstream": [
"CVE-2021-3573"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-3573"
]
},
"related_cves": [
{
"value": "CVE-2021-3573",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 421659,
"published_at": "2021-08-13T14:15:07.617+00:00"
}