CVE-2022-50733

Description

A use of uninitialized memory was found in the Linux kernel's idmouse USB fingerprint reader driver. In idmouse_create_image(), when any ftip_command() fails, control jumps to the reset label but leaves bulk_in_buffer data uninitialized. The subsequent check for a valid image then dereferences this uninitialized data, leading to undefined behavior.

Statement

This flaw was discovered by KMSAN (Kernel Memory Sanitizer) and affects systems with Siemens ID Mouse fingerprint readers. The uninitialized memory access occurs in an error handling path when USB commands fail. Exploitation requires physical access to connect a specific USB device and trigger the error condition.

Mitigation

To mitigate this issue, prevent the idmouse module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.5N/AN/A
Attack VectorLocalN/AN/A
Attack ComplexityLowN/AN/A
Privileges RequiredLowN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactNoneN/AN/A
Availability ImpactHighN/AN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

If the uninitialized pointer is used in a read operation, an attacker might be able to read sensitive portions of memory.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If the uninitialized pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If the uninitialized pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.

Frequently Asked Questions

Want to get errata notifications? Sign up here.