CVE-2021-47191
Description
A flaw was found in the Linux kernel's SCSI (Small Computer System Interface) debug driver. An improper validation of allocation length values in the resp_readcap16() function allows a local user to trigger an out-of-bounds memory read when processing specially crafted SCSI commands. This issue can cause a system crash, resulting in a Denial of Service (DoS), or potentially lead to unauthorized kernel information disclosure.
Statement
This vulnerability is rated as having a Low impact because the affected scsi_debug driver is intended solely for testing and debugging environments and is not loaded by default on Red Hat Enterprise Linux. Exploitation requires a local user to interact directly with simulated SCSI target devices, which typically requires elevated privileges or dedicated test configurations. Because production systems do not deploy this testing driver under standard operational conditions, the overall blast radius is minimal.
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 | 6 | 7.1 | 7.1 |
| Attack Vector | Local | Local | Local |
| Attack Complexity | Low | Low | Low |
| Privileges Required | High | Low | Low |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | High | High |
| Integrity Impact | None | None | None |
| Availability Impact | High | High | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
