CVE-2021-38166

In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.

CVSS 3.1

7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

0.3% chance of exploitation in the next 30 days; higher than 24% of CVEs (scores of 2026-10-25)

CWEs

CWE-190, CWE-787

Published

2021-08-07

Modified

2026-10-08

Record from

the NVD, synced 2026-10-19

Affected

• debian:debian_linux
• fedoraproject:fedora
• linux:linux_kernel

References

• https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=c4eb1f403243fc7bbb7de644db8587c03de36da6
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUVLBJKZMWA3E3YXSH4SZ7BOYGJP4GXP/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UL6CH5M5PRLMA3KPBX4LPUO6Z73GRISO/
• https://lore.kernel.org/bpf/20210806150419.109658-1-th.yasumatsu%40gmail.com/
• https://security.netapp.com/advisory/ntap-20210909-0001/

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