Use After Free in GNU Glibc
CVE-2021-33574
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.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.035 (89.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.029 · newest: 0.035 · change: +0.006
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- sourceware.org/bugzilla/show_bug.cgi (Exploit, Third Party Advisory, Issue Tracking)
- sourceware.org/bugzilla/show_bug.cgi (Issue Tracking)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- security.netapp.com/advisory/ntap-20210629-0005/ (Third Party Advisory)
- security.gentoo.org/glsa/202107-07 (vendor-advisory, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.debian.org/debian-lts-announce/2022/10/msg00021.html (mailing-list, Mailing List, Third Party Advisory)
- 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
- 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
Frequently asked questions
- What is CVE-2021-33574?
- CVE-2021-33574 is a critical-severity vulnerability in GNU Glibc, classified under Use After Free. CVSS score: 9.8/10. Published 2021-05-25.
- How severe is CVE-2021-33574?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2021-33574 known to be exploited?
- 11 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.