CVE-2021-4159

Description

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.

Category

4.4
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.01%
Vendor Advisory kernel.org
Affected: n/a kernel
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=2036024 issue tracking
https://access.redhat.com/security/cve/CVE-2021-4159 third party advisory
https://security-tracker.debian.org/tracker/CVE-2021-4159 third party advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=294f2fc6da27620a506e6c050241655459ccd6bd mailing list patch vendor advisory
https://lists.debian.org/debian-lts-announce/2022/10/msg00000.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-4159?
CVE-2021-4159 has been scored as a medium severity vulnerability.
How to fix CVE-2021-4159?
To fix CVE-2021-4159, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-4159 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-4159 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-4159?
CVE-2021-4159 affects n/a kernel.
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