CVE-2020-14311

Published: 29 July 2020

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.

From the Ubuntu security team

Chris Coulson discovered that multiple integer overflows existed in GRUB2 when handling certain filesystems, font files or PNG images, leading to heap-based buffer overflows. A local attacker could use these to execute arbitrary code and bypass UEFI Secure Boot restrictions.

Priority

High

CVSS 3 base score: 5.7

Status

Package Release Status
grub2
Launchpad, Ubuntu, Debian
Upstream Needs triage

Ubuntu 21.04 (Hirsute Hippo) Not vulnerable
(2.04-1ubuntu26.1)
Ubuntu 20.04 LTS (Focal Fossa)
Released (2.04-1ubuntu26.1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (2.02-2ubuntu8.16)
Ubuntu 16.04 ESM (Xenial Xerus)
Released (2.02~beta2-36ubuntu3.26)
Ubuntu 14.04 ESM (Trusty Tahr)
Released (2.02~beta2-9ubuntu1.20)
grub2-signed
Launchpad, Ubuntu, Debian
Upstream Needs triage

Ubuntu 21.04 (Hirsute Hippo) Not vulnerable
(1.147)
Ubuntu 20.04 LTS (Focal Fossa)
Released (1.142.3)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (1.93.18)
Ubuntu 16.04 ESM (Xenial Xerus)
Released (1.66.26)
Ubuntu 14.04 ESM (Trusty Tahr)
Released (1.34.22)