Critical
Security advisory
The mq_notify function in the GNU C Library (aka glibc) versions 2.32 and 2.33 has a use-after-free. It may use the notification thread attributes object (passed through its struct sigevent parameter) after it has been freed by the caller, leading to a denial of service (application crash) or possibly unspecified other impact.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-33574
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 06:11 UTC · Revision 1
Source evidence
The mq_notify function in the GNU C Library (aka glibc) versions 2.32 and 2.33 has a use-after-free. It may use the notification thread attributes object (passed through its struct sigevent parameter) after it has been freed by the caller, leading to a denial of service (application crash) or possibly unspecified other impact.
osv:CVE-2021-33574
Complete source record
{
"id": "d9319d7deda8263810051757f7264de703fc2e4e54f70dcd54845dd3b6f90ea5",
"url": "https://osv.dev/vulnerability/CVE-2021-33574",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-33574",
"summary": "The mq_notify function in the GNU C Library (aka glibc) versions 2.32 and 2.33 has a use-after-free. It may use the notification thread attributes object (passed through its struct sigevent parameter) after it has been freed by the caller, leading to a denial of service (application crash) or possibly unspecified other impact.",
"evidence": "osv:CVE-2021-33574",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2021-33574",
"aliases": [
"CVE-2021-33574"
],
"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/bminor/glibc",
"type": "GIT",
"events": [
{
"introduced": "3de512be7ea6053255afed6154db9ee31d4e557a"
},
{
"last_affected": "9826b03b747b841f5fc6de2054bf1ef3f5c4bdf3"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:gnu:glibc:2.32:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.32"
},
{
"last_affected": "2.32"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:gnu:glibc:2.33:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.33"
},
{
"last_affected": "2.33"
}
],
"source": "CPE_STRING"
}
]
}
}
],
"versions": [
"2.32",
"2.33",
"glibc-2.33",
"glibc-2.32",
"glibc-2.32.9000"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-33574.json"
}
},
{
"ranges": [
{
"repo": "https://sourceware.org/git/glibc.git",
"type": "GIT",
"events": [
{
"introduced": "3de512be7ea6053255afed6154db9ee31d4e557a"
},
{
"last_affected": "9826b03b747b841f5fc6de2054bf1ef3f5c4bdf3"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:gnu:glibc:2.32:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.32"
},
{
"last_affected": "2.32"
}
],
"source": "CPE_STRING"
},
{
"cpe": "cpe:2.3:a:gnu:glibc:2.33:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.33"
},
{
"last_affected": "2.33"
}
],
"source": "CPE_STRING"
}
]
}
}
],
"versions": [
"2.32",
"2.33",
"glibc-2.33",
"glibc-2.32",
"glibc-2.32.9000"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-33574.json"
}
}
],
"modified": "2026-10-24T10:30:36.467124290Z",
"provider": "osv",
"references": [
"https://cert-portal.siemens.com/productcert/html/ssa-398330.html",
"https://cert-portal.siemens.com/productcert/html/ssa-831302.html",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KJYYIMDDYOHTP2PORLABTOHYQYYREZDD/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RBUUWUGXVILQXVWEOU7N42ICHPJNAEUP/",
"https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html",
"https://security.gentoo.org/glsa/202107-07",
"https://security.netapp.com/advisory/ntap-20210629-0005/",
"https://sourceware.org/bugzilla/show_bug.cgi?id=27896",
"https://sourceware.org/bugzilla/show_bug.cgi?id=27896#c1"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:a:netapp:e-series_santricity_os_controller:*:*:*:*:*:*:*:*"
],
"vendor_product": "netapp:e-series_santricity_os_controller",
"extracted_events": [
{
"range": [
{
"introduced": "11.0"
},
{
"last_affected": "11.70.1"
}
],
"source": "CPE_RANGE"
}
]
},
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "10.0"
},
{
"last_affected": "10.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "33"
},
{
"last_affected": "33"
},
{
"introduced": "34"
},
{
"last_affected": "34"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2021-33574",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 433981,
"published_at": "2021-05-25T22:15:10.41+00:00"
}