CVE-2021-3735 : What You Need to Know
Discover the impact and technical details of CVE-2021-3735, a deadlock issue in QEMU's AHCI controller device, allowing a privileged user to cause denial of service.
A deadlock vulnerability was discovered in the AHCI controller device of QEMU, affecting system availability by allowing a privileged user to hang the QEMU process on the host, leading to a denial of service.
Understanding CVE-2021-3735
This section provides insights into the impact and technical details of the CVE.
What is CVE-2021-3735?
CVE-2021-3735 is a deadlock issue in the AHCI controller device of QEMU, triggered during a software reset while processing a specific packet from the guest, leading to a denial of service condition.
The Impact of CVE-2021-3735
The primary consequence of this vulnerability is the potential disruption of system availability due to a privileged user's ability to hang the QEMU process, thereby causing a denial of service.
Technical Details of CVE-2021-3735
Explore the vulnerability description, affected systems, and exploitation mechanism below.
Vulnerability Description
The vulnerability arises in the AHCI controller device of QEMU when processing a host-to-device Register FIS packet, allowing a guest user to trigger a deadlock situation.
Affected Systems and Versions
The deadlock issue impacts QEMU, specifically in the AHCI controller device. The exact affected versions are unspecified.
Exploitation Mechanism
By performing a software reset (ahci_reset_port) and manipulating a Register FIS packet, a privileged user within the guest environment can exploit this vulnerability to hang the QEMU process.
Mitigation and Prevention
Discover immediate steps and long-term security practices to safeguard against CVE-2021-3735.
Immediate Steps to Take
To mitigate the risk posed by CVE-2021-3735, consider applying vendor patches or updates, monitoring system logs for any suspicious activities, and restricting privileged access.
Long-Term Security Practices
Establishing a robust security posture involves regular security training for personnel, implementing defense-in-depth strategies, and staying informed about emerging threats in virtual environments.
Patching and Updates
Stay vigilant for security advisories from relevant vendors like Red Hat and apply recommended patches promptly to address known vulnerabilities.