CVE-2021-26930: High severity linux kernel vulnerability

Published Feb 17, 2021
·
Updated

An issue was discovered in the Linux kernel 3.11 through 5.10.16, as used by Xen. To service requests to the PV backend, the driver maps grant references provided by the frontend. In this process, errors may be encountered. In one case, an error encountered earlier might be discarded by later processing, resulting in the caller assuming successful mapping, and hence subsequent operations trying to access space that wasn't mapped. In another case, internal state would be insufficiently updated, preventing safe recovery from the error. This affects drivers/block/xen-blkback/blkback.c.

Affected Software

5 affected componentsFixes available
Linux Linux kernel>=3.11<=5.10.16
Fedoraproject Fedora=32
Fedoraproject Fedora=33
Debian Debian Linux=9.0
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.22-16.12.25-1

Event History

Feb 17, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Mar 28, 2024
Data Sourced
via Launchpad·12:23 AM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:25 AM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·04:25 AM
DescriptionAffected Software

Frequently Asked Questions

1

What are the potential impacts of CVE-2021-26930?

CVE-2021-26930 can lead to denial of service or memory corruption due to mishandling of grant references in the Linux kernel.

2

What is the severity of CVE-2021-26930?

CVE-2021-26930 is classified as a high severity vulnerability due to the risk of system instability.

3

Which versions of the Linux kernel are affected by CVE-2021-26930?

CVE-2021-26930 affects the Linux kernel versions from 3.11 through 5.10.16.

4

How do I fix CVE-2021-26930?

To mitigate CVE-2021-26930, update your Linux kernel to one of the fixed versions such as 5.10.223-1 or higher.

5

Is CVE-2021-26930 specific to any Linux distributions?

CVE-2021-26930 affects multiple distributions including Debian and Fedora, particularly versions using the affected Linux kernel.

Contact

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