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CVE-2021-33574The 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…
- 9.8CriticalCVSS base score
- 3.5%Exploitation in 30 daysEPSS · top 11% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
Published
- 5 years later
· 5 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 3.5% · top 11% of all CVEs (12 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
n/a
- affected n/a
References
References9
- https://sourceware.org/bugzilla/show_bug.cgi?id=27896 (opens in a new tab)x_transferred
- https://sourceware.org/bugzilla/show_bug.cgi?id=27896#c1 (opens in a new tab)x_transferred
- FEDORA-2021-7ddb8b0537 (opens in a new tab)vendor-advisoryx_transferred
- https://security.netapp.com/advisory/ntap-20210629-0005/ (opens in a new tab)x_transferred
- GLSA-202107-07 (opens in a new tab)vendor-advisoryx_transferred
- FEDORA-2021-f29b4643c7 (opens in a new tab)vendor-advisoryx_transferred
- [debian-lts-announce] 20221017 [SECURITY] [DLA 3152-1] glibc security update (opens in a new tab)mailing-listx_transferred
- https://cert-portal.siemens.com/productcert/html/ssa-831302.html (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-20261 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-33574)Record last updated .