Go to homepageCyberStrike

Menu

Star on GitHub · 3.2k
Sign inDownload

CVE-2021-26931

5.5 · MEDIUM

An issue was discovered in the Linux kernel 2.6.39 through 5.10.16, as used in Xen.

Published Feb 17, 2021CWE-770EPSS 0.56%

Overview

CVE-2021-26931 is a medium-severity vulnerability. It was published on February 17, 2021 and has a CVSS 3.1 base score of 5.5 (MEDIUM).

This vulnerability has a CVSS 3.1 base score of 5.5, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.

Technical description

An issue was discovered in the Linux kernel 2.6.39 through 5.10.16, as used in Xen. Block, net, and SCSI backends consider certain errors a plain bug, deliberately causing a kernel crash. For errors potentially being at least under the influence of guests (such as out of memory conditions), it isn't correct to assume a plain bug. Memory allocations potentially causing such crashes occur only when Linux is running in PV mode, though. This affects drivers/block/xen-blkback/blkback.c and drivers/xen/xen-scsiback.c.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References

Refxenbits.xen.org/xsa/advisory-362.htmlRefgit.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3194a1746e8aabe86075fd3c5e7cf1f4632d7f16Refgit.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5a264285ed1cd32e26d9de4f3c8c6855e467fd63Refgit.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7c77474b2d22176d2bfb592ec74e0f2cb71352c9Reflists.debian.org/debian-lts-announce/2021/03/msg00010.htmlReflists.debian.org/debian-lts-announce/2021/03/msg00035.htmlReflists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2XQR52ICKRK3GC4HDWLMWF2U55YGAR63/Reflists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GWQWPWYZRXVFJI5M3VCM72X27IB7CKOB/Refsecurity.netapp.com/advisory/ntap-20210326-0001/Refxenbits.xen.org/xsa/advisory-362.html

How CyberStrike helps

Frequently asked questions

What is CVE-2021-26931?

CVE-2021-26931 is a medium-severity vulnerability. It was published on February 17, 2021 and has a CVSS 3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-26931?

This vulnerability has a CVSS 3.1 base score of 5.5, rated MEDIUM. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.

How do I fix or remediate CVE-2021-26931?

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2021-26931?

CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2021-26931 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.

Related MEDIUM CVEs from 2021

View all
Browse by year2026202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999