CVE-2021-3507: Buffer Overflow

Published Apr 19, 2021
·
Updated

A heap buffer overflow was found in the floppy disk emulator of QEMU up to 6.0.0 (including). It could occur in fdctrltransferhandler() in hw/block/fdc.c while processing DMA read data transfers from the floppy drive to the guest system. A privileged guest user could use this flaw to crash the QEMU process on the host resulting in DoS scenario, or potential information leakage from the host memory.

Affected Software

6 affected componentsFixes available
Qemu Qemu<=6.0.0
Debian Debian Linux=10.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux=8.0
debian/qemu<=1:5.2+dfsg-11+deb11u2
1:5.2+dfsg-11+deb11u31:7.2+dfsg-7+deb12u121:10.0.0~rc2+ds-21:10.0.0~rc3+ds-2
Microsoft cm1 qemu-kvm 4.2.0-48

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/qemu to a version that resolves this vulnerability.

    Fixed in 1:5.2+dfsg-11+deb11u3Fixed in 1:7.2+dfsg-7+deb12u12Fixed in 1:10.0.0~rc2+ds-2Fixed in 1:10.0.0~rc3+ds-2

Event History

Apr 19, 2021
Data Sourced
via Red Hat·04:50 PM
DescriptionSeverityAffected Software
May 6, 2021
CVE Published
via MITRE·03:16 PM
Data Sourced
via MITRE·03:16 PM
DescriptionWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:57 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·01:48 AM
RemedyDescriptionSeverityAffected Software
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 vulnerability ID for this heap buffer overflow in QEMU?

The vulnerability ID is CVE-2021-3507.

2

In which version of QEMU does this heap buffer overflow vulnerability exist?

This heap buffer overflow vulnerability exists in QEMU up to version 6.0.0 (including).

3

What is the severity rating of CVE-2021-3507?

CVE-2021-3507 has a severity rating of 6.1 (Medium).

4

How does this heap buffer overflow vulnerability in QEMU impact the system?

This heap buffer overflow vulnerability in QEMU could allow a privileged guest user to crash the QEMU process.

5

Are there any known solutions or fixes for CVE-2021-3507?

Yes, you can find more information about available remedies or fixes for CVE-2021-3507 in the provided references.

Contact

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