CVE-2020-8647
Description
A flaw was found in the Linux kernel’s virtual console resize functionality. An attacker with local access to virtual consoles can use the virtual console resizing code to gather kernel internal data structures.
Statement
This flaw is rated as having Moderate impact because the information leak is limited.
Mitigation
The attack vector can be significantly reduced by preventing users from being able to log into the local virtual console.
See the instructions on disabling local login here: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/managing_smart_cards/pam_configuration_files , See the section on "pam_console" to deny users logging into the console. This mechanism should work from el6 forward to current versions of Red Hat Enterprise Linux.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.1 | 6.1 | 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 | Low | Low | 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:L/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Red Hat CVSS v3 Score Explanation
The attacker may be able to possibly leak from the slab, but the read value is not controlled and the attacker only has access to slab memory located adjacent to the old console buffer.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Frequently Asked Questions
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