CVE-2020-35503: Null Pointer Dereference

Published Dec 23, 2020
·
Updated

A NULL pointer dereference flaw was found in the megasas-gen2 SCSI host bus adapter emulation of QEMU in versions before and including 6.0. This issue occurs in the megasascommandcancelled() callback function while dropping a SCSI request. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Other sources

A NULL pointer dereference issue was found in the megasas-gen2 SCSI host bus adapter emulation of QEMU. It could occur in the megasascommandcancelled() callback function in hw/scsi/megasas.c while dropping a SCSI request. A privileged guest user may exploit this issue to crash the QEMU process on the host, resulting in a denial of service condition.

Red Hat

Affected Software

3 affected componentsFixes available
Qemu Qemu<=6.0.0
Fedoraproject Fedora=33
Microsoft cm1 qemu-kvm 4.2.0-48

Event History

Dec 23, 2020
Data Sourced
via Red Hat·02:32 PM
DescriptionSeverityAffected Software
Jun 2, 2021
CVE Published
via MITRE·01:22 PM
Data Sourced
via MITRE·01:22 PM
DescriptionWeakness
Oct 1, 2025
Data Sourced
via Microsoft·11:11 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·11:11 PM
Affected Software
Updated
via Microsoft·11:11 PM
DescriptionSeverity

Frequently Asked Questions

1

What is the severity of CVE-2020-35503?

CVE-2020-35503 is considered a moderate severity vulnerability as it can lead to a denial of service due to a NULL pointer dereference.

2

How do I fix CVE-2020-35503?

To fix CVE-2020-35503, update QEMU to version 6.0.1 or later, which addresses this specific vulnerability.

3

Which versions of QEMU are affected by CVE-2020-35503?

CVE-2020-35503 affects QEMU versions up to and including 6.0.0.

4

Can a privileged guest user exploit CVE-2020-35503?

Yes, a privileged guest user can exploit CVE-2020-35503 to crash the QEMU process.

5

What systems are impacted by CVE-2020-35503?

CVE-2020-35503 impacts QEMU and Fedora 33, which runs the affected versions of QEMU.

Contact

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