CVE-2021-38604
CVSS v3
7.5
HIGH
EPSS Score
3.0 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
In librt in the GNU C Library (aka glibc) through 2.34, sysdeps/unix/sysv/linux/mq_notify.c mishandles certain NOTIFY_REMOVED data, leading to a NULL pointer dereference. NOTE: this vulnerability was introduced as a side effect of the CVE-2021-33574 fix.
Technical details
- Published
- 2021-08-12
Frequently asked questions
What is CVE-2021-38604?
In librt in the GNU C Library (aka glibc) through 2.34, sysdeps/unix/sysv/linux/mq_notify.c mishandles certain NOTIFY_REMOVED data, leading to a NULL pointer dereference. NOTE: this vulnerability was introduced as a side effect of the CVE-2021-33574 fix.
Is CVE-2021-38604 actively exploited?
Active exploitation of CVE-2021-38604 has not been confirmed. Its EPSS score was 3.0% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-38604?
CVE-2021-38604 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-38604 affecting your environment?
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