CVE-2026-64351
Description
A flaw was found in the Linux kernel's USB Kalmia driver. An attacker with a specially crafted USB device could exploit an out-of-bounds read vulnerability in the kalmia_rx_fixup() function. This occurs due to an incorrect calculation of the USB packet length when processing short bulk-IN frames, leading to a memory underflow. This flaw could allow an attacker to read sensitive information from outside the intended memory buffer or potentially cause a denial of service.
Statement
This vulnerability is rated as Moderate impact because exploitation requires local access through a physically attached malicious USB device or device passthrough in virtualized environments, rather than exposing systems to remote network attack. The risk is confined to systems utilizing the specialized Kalmia USB modem driver, which is uncommon in enterprise deployments. Consequently, an attacker cannot trigger kernel memory leaks or a denial of service without direct interaction with the host USB subsystem.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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