CVE-2021-3930: Medium severity Qemu Qemu vulnerability
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
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/qemu-kvmto a version that resolves this vulnerability.Fixed in 6.2.0 - Upgrade
Upgrade
debian/qemuto a version that resolves this vulnerability.Fixed in 1:5.2+dfsg-11+deb11u3Fixed in 1:7.2+dfsg-7+deb12u12Fixed in 1:9.2.2+ds-1Fixed in 1:10.0.0~rc1+ds-2 - Upgrade
Upgrade
alpine/qemuto a version that resolves this vulnerability.Fixed in 6.1.1-r0
Event History
Frequently Asked Questions
What is CVE-2021-3930?
CVE-2021-3930 is an off-by-one error found in the SCSI device emulation in QEMU.
How does CVE-2021-3930 affect QEMU?
CVE-2021-3930 could potentially crash QEMU, resulting in a denial of service condition.
Which software versions are affected by CVE-2021-3930?
QEMU versions up to and excluding 6.2.0 are affected by CVE-2021-3930.
What is the severity of CVE-2021-3930?
CVE-2021-3930 has a severity rating of 6.5 (medium).
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.