Auth bypass in Linux Kernel

CVE-2021-31829

kernel/bpf/verifier.c in the Linux kernel through 5.12.1 performs undesirable speculative loads, leading to disclosure of stack content via side-channel attacks, aka CID-801c6058d14a. The specific concern is not protecting the BPF stack area against speculative loads. Also, the BPF stack can contain uninitialized data that might represent sensitive information previously operated on by the kernel.

Vulnerability class: Broken Access Control

EPSS: 0.003 (23.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-31829?
CVE-2021-31829 is a medium-severity vulnerability in Linux Kernel, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2021-05-06.
How severe is CVE-2021-31829?
Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2021-31829 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.