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TI-2021-03030 Aliases CVE-2021-4159GHSA-4f4x-m5ww-4mcw

A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data…

Priority LOW 20CWE-202Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data structures. Internal memory locations could be returned to userspace. A local attacker with the permissions to insert eBPF code to the kernel can use this to leak internal kernel memory details defeating some of the exploit mitigations in place for the kernel.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00248 16th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—kernelFixed in v5.7-rc1—No fix listedCNA
  • kernel Vendor— Affected Fixed in v5.7-rc1 Fixed in — No fix listed CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 5.7VulnerableLinux
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*8.0VulnerableRed Hat
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.7 Vulnerable ·Linux
  • cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise MRG 2Affected—
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-4159
  2. 2026-10-03 Alias added: GHSA-4f4x-m5ww-4mcw
  3. 2026-11-02 CISA SSVC decision points changed

References

Patch 1

Advisory 3

Other 1

Sources

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