External risk intelligence

Linux Kernel SCSI Use-After-Free Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2022-48666

This vulnerability exists within internal Linux kernel SCSI storage subsystems. It is a low-level kernel memory management issue related to command privatization and device release, not exposed to or reachable from the network in any typical deployment scenario.

Use After Free

Linux Kernel

5.7 to before 5.19.126.0

Halo Surface Signal: 1 out of 5 — much less likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This vulnerability is a memory management issue within the Linux kernel's SCSI subsystem, specifically a use-after-free flaw. While the technical details involve complex kernel operations, the core problem relates to how certain commands are handled during device removal. The main concern is confirming whether this internal kernel issue has any relevance or exposure within our specific environment.

Kernel memory flaw, command release problem.
Matters if internal systems use specific SCSI functions.
Confirm relevance and exposure to our environment.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by triggering a specific sequence of SCSI operations within the Linux kernel. This could happen if the system is configured in a way that involves multipath devices and the SCSI command privatization exit points are mishandled. Successful exploitation could lead to memory corruption, potentially allowing an attacker to gain elevated privileges or cause a system crash.

Entry condition: Malformed SCSI commands or device management operations.
Trigger point: Improper handling of SCSI host resources during exit.
Resulting risk: Memory corruption and potential system instability.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability in the Linux kernel's SCSI subsystem could potentially lead to system instability or crashes. It stems from a use-after-free condition during the handling of SCSI host resources, which may occur during specific storage device removal operations.

SCSI host resources and system integrity are at risk.
Could happen during storage device removal.
May cause system instability or crashes.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability resides within the Linux kernel's SCSI storage subsystem, specifically addressing a use-after-free issue during resource management. Given its low-level nature and lack of direct network exposure, the primary responsibility likely falls to infrastructure or platform teams managing the core operating system. The initial practical step involves identifying all systems running the affected kernel versions and assessing their criticality, before engaging with relevant teams to plan a controlled remediation.

Infrastructure and Platform teams own remediation.
Verify affected kernel versions and system criticality.
Plan system updates during maintenance windows.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the Linux kernel in the context of CVE-2022-48666?

The Linux kernel is the core foundation of an operating system that manages hardware resources. In this advisory, the vulnerability specifically affects the SCSI (Small Computer System Interface) subsystem, which is the layer responsible for managing communication with storage devices like hard drives and solid-state drives.

What is a use-after-free vulnerability?

A use-after-free is a type of memory flaw categorized as CWE-416. It occurs when a program continues to use a pointer to a memory location after that memory has already been freed or released. In this case, the kernel improperly accesses SCSI resource data that is no longer valid, which can lead to system instability or memory corruption.

How is this vulnerability triggered?

This flaw is triggered during specific storage operations, specifically when a SCSI device is being removed from the system. It occurs if the kernel attempts to access SCSI host resources that have already been cleaned up. It is not triggered by standard file access or general network traffic; it requires complex, internal kernel-level storage management actions.

Do I need to worry about network-based attacks for this CVE?

According to Halo Surface Signal, this vulnerability is considered very unlikely to be exploited via the network. It exists deep within internal kernel storage management subsystems. Because it relates to low-level device release operations, it is not reachable from the network in any typical deployment scenario.

What is the first step to address this kernel issue?

The first step is to identify which of your systems are running the affected Linux kernel versions, specifically those within the 5.7 to 5.19 range or certain 6.0-rc builds. Once identified, infrastructure or platform teams should assess the criticality of these systems and schedule kernel updates according to your standard maintenance processes.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.