CVE-2022-3775

Description

A flaw was found in the grub2 font code. When rendering certain unicode sequences, it fails to properly validate the font width and height. These values are further used to access the font buffer, causing possible out-of-bounds writes. A malicious actor may craft a font capable of triggering this issue, allowing modifications in unauthorized memory segments, causing data integrity problems or leading to denial of service.

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 Score7.17.17.1
Attack VectorLocalLocalLocal
Attack ComplexityLowLowLow
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneNone
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

Vector

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

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

cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Understanding the Weakness (CWE)

Integrity

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands

Write operations could cause memory corruption. In some cases, an adversary can modify control data such as return addresses in order to execute unexpected code.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

Attempting to access out-of-range, invalid, or unauthorized memory could cause the product to crash.

Other

Technical Impact: Unexpected State

Subsequent write operations can produce undefined or unexpected results.

Acknowledgements

Red Hat would like to thank Daniel Axtens for reporting this issue.

Frequently Asked Questions

Want to get errata notifications? Sign up here.