CVE-2021-3930: Medium severity qemu vulnerability

Published Nov 5, 2021
·
Updated

An off-by-one error was found in the SCSI Device emulation in QEMU. It could occur in hw/scsi/scsi-disk.c:modesensepage() while processing MODE SELECT commands if 'page' was set to MODEPAGEALLS (0x3f). Specifically, 'page' was used to index the stack-allocated 'modesensevalid' buffer (size=0x3f), causing an off-by-one error when trying to access the last element. A malicious guest could use this flaw to potentially crash QEMU, resulting in a denial of service condition.

Other sources

An off-by-one error was found in the SCSI device emulation in QEMU. It could occur while processing MODE SELECT commands in modesensepage() if the 'page' argument was set to MODEPAGEALLS (0x3f). A malicious guest could use this flaw to potentially crash QEMU, resulting in a denial of service condition.

Launchpad

Affected Software

14 affected componentsFixes available
redhat/qemu-kvm<6.2.0
6.2.0
Qemu Qemu<6.2.0
redhat Codeready Linux Builder=8.0
redhat Codeready Linux Builder For Ibm Z Systems=8.0
redhat Codeready Linux Builder For Power Little Endian=8.0
redhat Openstack=10
redhat Openstack=13
redhat Enterprise Linux=8.0
redhat Enterprise Linux Advanced Virtualization Eus=8.4
redhat Enterprise Linux For Ibm Z Systems=8.0
redhat Enterprise Linux For Power Little Endian=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
debian/qemu<=1:5.2+dfsg-11+deb11u2
1:5.2+dfsg-11+deb11u31:7.2+dfsg-7+deb12u121:9.2.2+ds-11:10.0.0~rc1+ds-2

Event History

Feb 18, 2022
CVE Published
via MITRE·05:50 PM
Data Sourced
via MITRE·05:50 PM
DescriptionWeakness
Jan 12, 2024
Data Sourced
via Launchpad·12:00 AM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:34 AM
RemedyDescriptionSeverityAffected Software
Mar 31, 2025
Data Sourced
via Debian·01:07 AM
DescriptionAffected Software
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Frequently Asked Questions

1

What is CVE-2021-3930?

CVE-2021-3930 is an off-by-one error found in the SCSI device emulation in QEMU.

2

How does CVE-2021-3930 affect QEMU?

CVE-2021-3930 could potentially crash QEMU, resulting in a denial of service condition.

3

Which software versions are affected by CVE-2021-3930?

QEMU versions up to and excluding 6.2.0 are affected by CVE-2021-3930.

4

What is the severity of CVE-2021-3930?

CVE-2021-3930 has a severity rating of 6.5 (medium).

5

Where can I find more information about CVE-2021-3930?

You can find more information about CVE-2021-3930 on the Red Hat Bugzilla and NetApp security advisory websites, as well as the Debian LTS announce mailing list.

Contact

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