CVE-2021-3735

Description

A deadlock issue was found in the AHCI controller device of QEMU. It occurs on a software reset (ahci_reset_port) while handling a host-to-device Register FIS (Frame Information Structure) packet from the guest. A privileged user inside the guest could use this flaw to hang the QEMU process on the host, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability.

Categories

4.4
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.02%
Third-Party Advisory redhat.com Third-Party Advisory redhat.com Third-Party Advisory debian.org
Affected: n/a QEMU
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1997184 third party advisory issue tracking
https://access.redhat.com/security/cve/CVE-2021-3735 third party advisory
https://security-tracker.debian.org/tracker/CVE-2021-3735 third party advisory
https://security.netapp.com/advisory/ntap-20250228-0009/

Frequently Asked Questions

What is the severity of CVE-2021-3735?
CVE-2021-3735 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3735?
To fix CVE-2021-3735, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3735 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3735 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3735?
CVE-2021-3735 affects n/a QEMU.
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