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Vulnerability · Published May 25, 2021 · Assigned by mitre

CVE-2021-33574

Critical 9.8

In plain English

A critical-severity security flaw in the compat-libpthread-nonshared package (AlmaLinux). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 3.5% (higher than 89% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)9.8Critical
Exploit odds (30 days)3.5%top 10.7% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8compat-libpthread-nonshared2.28-164.el8ALSA-2021:4358
AlmaLinux:8glibc-benchtests2.28-164.el8ALSA-2021:4358
AlmaLinux:8glibc-nss-devel2.28-164.el8ALSA-2021:4358
AlmaLinux:8glibc-static2.28-164.el8ALSA-2021:4358
AlmaLinux:8glibc-utils2.28-164.el8ALSA-2021:4358
AlmaLinux:8nss_hesiod2.28-164.el8ALSA-2021:4358
Debian:12glibc2.32-1DEBIAN-CVE-2021-33574
Debian:13glibc2.32-1DEBIAN-CVE-2021-33574
Debian:14glibc2.32-1DEBIAN-CVE-2021-33574
Rocky Linux:8glibc0:2.28-164.el8RLSA-2021:4358

Affected products (as reported)

VendorProductVersions
n/a n/a n/a

References