CVE-2020-14311: There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32_MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow.

Overview

Severity

Medium (CVSS 5.7)

CVSS Vector

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

Exploit Status

Not Exploited

Patch Tuesday

2020-Jul

Released

2020-09-25

Last Updated

2026-02-19

EPSS Score

0.03% (percentile: 9.2%)

FAQ

Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability? One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.

Affected Products (3)

Other

• 19663-17084
• 19130-16820
• 19072-16823

Revision History

• 2020-09-25: Information published.
• 2021-12-16: Added grub2 to CBL-Mariner 2.0
• 2025-07-11: Added grub2 to Azure Linux 3.0 Added grub2 to CBL-Mariner 1.0 Added grub2 to CBL-Mariner 2.0
• 2026-02-19: Information published.