---
id: CVE-2021-38604
title: >-
  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
summary: >-
  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 CV…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
  - CWE-476
vendor: gnu
product: glibc
affected:
  - glibc <= 2.34
  - fedora = 35
  - communications_cloud_native_core_binding_support_function = 22.1.3
  - >-
    communications_cloud_native_core_network_function_cloud_native_environment =
    22.1.0
  - communications_cloud_native_core_network_repository_function = 22.1.2
  - communications_cloud_native_core_network_repository_function = 22.2.0
  - communications_cloud_native_core_security_edge_protection_proxy = 22.1.1
  - communications_cloud_native_core_unified_data_repository = 22.2.0
  - enterprise_operations_monitor = 4.3
  - enterprise_operations_monitor = 4.4
  - enterprise_operations_monitor = 5.0
published: '2021-08-12'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T12:17:15.650'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-38604'
references:
  - url: >-
      https://blog.tuxcare.com/cve/tuxcare-team-identifies-cve-2021-38604-a-new-vulnerability-in-glibc
    label: cve@mitre.org
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GYEXYM37RCJWJ6B5KQUYQI4NZBDDYSXP/
    label: cve@mitre.org
  - url: 'https://security.gentoo.org/glsa/202208-24'
    label: cve@mitre.org
  - url: 'https://security.netapp.com/advisory/ntap-20210909-0005/'
    label: cve@mitre.org
  - url: 'https://sourceware.org/bugzilla/show_bug.cgi?id=28213'
    label: cve@mitre.org
  - url: >-
      https://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=4cc79c217744743077bf7a0ec5e0a4318f1e6641
    label: cve@mitre.org
  - url: >-
      https://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=b805aebd42364fe696e417808a700fdb9800c9e8
    label: cve@mitre.org
  - url: 'https://www.oracle.com/security-alerts/cpujul2022.html'
    label: cve@mitre.org
  - url: >-
      https://blog.tuxcare.com/cve/tuxcare-team-identifies-cve-2021-38604-a-new-vulnerability-in-glibc
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GYEXYM37RCJWJ6B5KQUYQI4NZBDDYSXP/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.gentoo.org/glsa/202208-24'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20210909-0005/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://sourceware.org/bugzilla/show_bug.cgi?id=28213'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=4cc79c217744743077bf7a0ec5e0a4318f1e6641
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=b805aebd42364fe696e417808a700fdb9800c9e8
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.oracle.com/security-alerts/cpujul2022.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-831302.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
epss: 0.03045
epssPercentile: 0.87209
ingestedAt: '2026-10-14T12:29:10.825Z'
---

## Overview

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.

## Affected

- `glibc <= 2.34`
- `fedora = 35`
- `communications_cloud_native_core_binding_support_function = 22.1.3`
- `communications_cloud_native_core_network_function_cloud_native_environment = 22.1.0`
- `communications_cloud_native_core_network_repository_function = 22.1.2`
- `communications_cloud_native_core_network_repository_function = 22.2.0`
- `communications_cloud_native_core_security_edge_protection_proxy = 22.1.1`
- `communications_cloud_native_core_unified_data_repository = 22.2.0`
- `enterprise_operations_monitor = 4.3`
- `enterprise_operations_monitor = 4.4`
- `enterprise_operations_monitor = 5.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.