CVE-2021-3607 : Vulnerability Insights and Analysis

An integer overflow vulnerability was discovered in the QEMU implementation of VMWare's paravirtual RDMA device in versions prior to 6.1.0. This flaw can be exploited by a privileged guest user to trigger a denial of service attack by allocating a large amount of memory.

Understanding CVE-2021-3607

This section dives into the details of the CVE-2021-3607 vulnerability.

What is CVE-2021-3607?

The CVE-2021-3607 vulnerability is an integer overflow issue in QEMU's implementation of VMWare's paravirtual RDMA device, affecting versions before 6.1.0. Improper input validation during the handling of specific writes from the guest can lead to a denial of service.

The Impact of CVE-2021-3607

The highest risk posed by CVE-2021-3607 is to system availability, as a privileged guest user can exploit the vulnerability to exhaust system memory, causing a denial of service.

Technical Details of CVE-2021-3607

This section outlines the technical aspects of CVE-2021-3607.

Vulnerability Description

The vulnerability arises from an integer overflow in the QEMU implementation, triggered by handling specific guest writes. This allows a guest user to force QEMU to allocate excessive memory, leading to a denial of service condition.

Affected Systems and Versions

QEMU versions prior to 6.1.0 that implement VMWare's paravirtual RDMA device are affected by CVE-2021-3607.

Exploitation Mechanism

By sending malicious inputs, a privileged guest user can exploit the integer overflow in QEMU to trigger the vulnerability and cause a denial of service attack.

Mitigation and Prevention

Here's how you can mitigate and prevent the CVE-2021-3607 vulnerability.

Immediate Steps to Take

Update QEMU to version 6.1.0 or above to patch the vulnerability.
Monitor and restrict guest user activities to prevent exploitation.

Long-Term Security Practices

Regularly apply security updates to QEMU and related software.
Educate users on secure practices to minimize the risk of exploitation.

Patching and Updates

Stay informed about security advisories and promptly apply patches to protect systems from vulnerabilities like CVE-2021-3607.