CVE-2021-4002

Public Exploit

Description

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.

Categories

4.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.01%
Vendor Advisory debian.org Vendor Advisory kernel.org Vendor Advisory kernel.org
Affected: n/a kernel
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=2025726 third party advisory issue tracking
https://www.openwall.com/lists/oss-security/2021/11/25/1 mailing list third party advisory exploit
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=13e4ad2ce8df6e058ef482a31fdd81c725b0f7ea patch vendor advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a4a118f2eead1d6c49e00765de89878288d4b890 patch vendor advisory
https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html third party advisory mailing list
https://www.debian.org/security/2022/dsa-5096 third party advisory vendor advisory
https://www.oracle.com/security-alerts/cpujul2022.html third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-4002?
CVE-2021-4002 has been scored as a medium severity vulnerability.
How to fix CVE-2021-4002?
To fix CVE-2021-4002, 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-2021-4002 being actively exploited in the wild?
It is possible that CVE-2021-4002 is being exploited or will be exploited in a near future based on public information. 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-2021-4002?
CVE-2021-4002 affects n/a kernel.
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