CVE-2019-12068 : Security Advisory and Response

In QEMU versions 1:4.1-1, 1:2.1+dfsg-12+deb8u6, 1:2.8+dfsg-6+deb9u8, 1:3.1+dfsg-8~deb10u1, 1:3.1+dfsg-8+deb10u2, and 1:2.1+dfsg-12+deb8u12, a potential issue exists in the execution of a script in the LSI SCSI adapter emulator.

Understanding CVE-2019-12068

This CVE involves a vulnerability in the LSI SCSI adapter emulator in QEMU versions, potentially leading to an infinite loop under specific conditions.

What is CVE-2019-12068?

In QEMU, a script execution in the LSI SCSI adapter emulator can trigger an infinite loop if the next opcode is empty, affecting specific versions of the software.

The Impact of CVE-2019-12068

The vulnerability could allow an attacker to exploit the infinite loop condition, potentially leading to denial of service or other malicious activities.

Technical Details of CVE-2019-12068

This section provides more in-depth technical insights into the CVE.

Vulnerability Description

The issue arises in the lsi_execute_script() function of the LSI SCSI adapter emulator, where advancing the 's->dsp' index to read the next opcode can result in an infinite loop if the next opcode is empty.

Affected Systems and Versions

QEMU versions 1:4.1-1, 1:2.1+dfsg-12+deb8u6, 1:2.8+dfsg-6+deb9u8, 1:3.1+dfsg-8~deb10u1, 1:3.1+dfsg-8+deb10u2, and 1:2.1+dfsg-12+deb8u12

Exploitation Mechanism

The vulnerability can be exploited by executing a script in the LSI SCSI adapter emulator with specific conditions that trigger the infinite loop.

Mitigation and Prevention

It is crucial to take immediate steps to address and prevent the exploitation of CVE-2019-12068.

Immediate Steps to Take

Update QEMU to the fixed version that addresses the infinite loop issue.
Monitor and restrict script executions in the LSI SCSI adapter emulator.

Long-Term Security Practices

Regularly update and patch QEMU and other software components to prevent vulnerabilities.
Implement proper input validation and error handling mechanisms in emulator scripts.

Patching and Updates

Apply the necessary security updates provided by QEMU to mitigate the CVE-2019-12068 vulnerability.