Buffer overflow in Qemu

CVE-2021-3507

A heap buffer overflow was found in the floppy disk emulator of QEMU up to 6.0.0 (including). It could occur in fdctrl_transfer_handler() 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.

Vulnerability class: Buffer Overflow

EPSS: 0.005 (39.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-3507?
CVE-2021-3507 is a medium-severity vulnerability in Qemu, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.1/10. Published 2021-05-06.
How severe is CVE-2021-3507?
Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2021-3507 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.