CVE-2021-27364 : Exploit Details and Defense Strategies

An issue was discovered in the Linux kernel through 5.11.3. A vulnerability in drivers/scsi/scsi_transport_iscsi.c allows an unprivileged user to craft Netlink messages.

Understanding CVE-2021-27364

This CVE describes a security issue in the Linux kernel that can be exploited by a local unprivileged user.

What is CVE-2021-27364?

CVE-2021-27364 is a vulnerability in the Linux kernel that affects versions up to 5.11.3. It arises from a flaw in the handling of Netlink messages in drivers/scsi/scsi_transport_iscsi.c.

The Impact of CVE-2021-27364

The vulnerability allows an attacker with local access to escalate privileges by exploiting the flaw in Netlink message crafting. This could lead to unauthorized access and potential system compromise.

Technical Details of CVE-2021-27364

The following technical aspects are associated with CVE-2021-27364:

Vulnerability Description

The vulnerability in drivers/scsi/scsi_transport_iscsi.c in Linux kernel versions up to 5.11.3 enables an unprivileged user to manipulate Netlink messages, potentially leading to privilege escalation.

Affected Systems and Versions

All Linux kernel versions up to 5.11.3 are affected by this vulnerability. Systems running these versions are at risk of exploitation.

Exploitation Mechanism

By crafting malicious Netlink messages, an unprivileged user can exploit the flaw within drivers/scsi/scsi_transport_iscsi.c to gain elevated privileges on the system.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-27364, consider the following steps:

Immediate Steps to Take

Apply security patches provided by the Linux kernel maintainers.
Monitor system logs for any suspicious activity.
Restrict unprivileged user access to critical system components.

Long-Term Security Practices

Keep your Linux kernel up to date with the latest security patches.
Implement least privilege access controls to limit user capabilities.
Conduct regular security audits to detect and address any vulnerabilities in a timely manner.

Patching and Updates

Ensure timely installation of security updates released by the Linux kernel development team to address CVE-2021-27364 and other known vulnerabilities.