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TI-2021-02899 Aliases CVE-2021-4002GHSA-7jmv-5cqq-75jg

Memory leak in kernel

Priority LOW 21CWE-459Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
Low · Low · None
Fix status
Partial Red Hat: 4 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-401.

Summary

A memory leak flaw in the Linux kernel's hugetlbfs memory usage was found in the way the user maps some regions of memory twice using shmget() which are aligned to PUD alignment with the fault of some of the memory pages. A local user could use this flaw to get unauthorized access to some data.

Why it matters now

EPSS 0.00515 44th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 2 advisoriesRed Hat: 4 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—kernelaffects kernel v3.6 and later through v5.15.5.—No fix listedCNA
  • kernel Vendor— Affected affects kernel v3.6 and later through v5.15.5. Fixed in — No fix listed CNA

CPE configurations NVD · 10

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 5.16VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.16:-:*:*:*:*:*:*5.16VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*5.16 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:*5.16 rc2VulnerableLinux
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*35VulnerableFedoraproject
cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:22.1.3:*:*:*:*:*:*:*22.1.3VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_network_exposure_function:22.1.1:*:*:*:*:*:*:*22.1.1VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_policy:22.2.0:*:*:*:*:*:*:*22.2.0VulnerableOracle
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.16 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.16:-:*:*:*:*:*:* Versions 5.16 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:* Versions 5.16 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:* Versions 5.16 rc2 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* Versions 35 Vulnerable ·Fedoraproject
  • cpe:2.3:a:oracle:communications_cloud_native_core_binding_support_function:22.1.3:*:*:*:*:*:*:* Versions 22.1.3 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_network_exposure_function:22.1.1:*:*:*:*:*:*:* Versions 22.1.1 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_policy:22.2.0:*:*:*:*:*:*:* Versions 22.2.0 Vulnerable ·Oracle

Remediation

Red Hat 2 advisories

  • RHSA-2022:1988 Released 2022-05-10 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-372.9.1.el8, kernel-4.18.0-372.9.1.el8, kernel-abi-stablelists-4.18.0-372.9.1.el8 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-372.9.1.el8
  • RHSA-2022:1975 Released 2022-05-10 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-372.9.1.rt7.166.el8, kernel-rt-core-4.18.0-372.9.1.rt7.166.el8, kernel-rt-debug-4.18.0-372.9.1.rt7.166.el8 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-372.9.1.rt7.166.el8, kernel-rt-core-4.18.0-372.9.1.rt7.166.el8, kernel-rt-debug-4.18.0-372.9.1.rt7.166.el8 +7

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2022:1988
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2022:1988
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2022:1975
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2022:1975
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-4002
  2. 2026-10-03 Alias added: GHSA-7jmv-5cqq-75jg

References

Exploit 1

Patch 3

Advisory 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences