The mq_notify function in the GNU C Library (aka glibc) through 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. CREATE(Triage):(User=admin) CVE-2021-33574 (https://nvd.nist.gov/vuln/detail/CVE-2021-33574)