PT-2020-3623 · Gnu+7 · Grub2+7

Chris Coulson · Published 2020-07-29 · Updated 2022-09-20 · CVE-2020-14311

Positive Technologies (AI Summary)

CVSS v3.1

6.0

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions grub2 versions prior to 2.06

Description The issue is related to a buffer overflow when handling symbolic links in ext filesystems. An arithmetic overflow occurs when a filesystem contains a symbolic link with an inode size of UINT32 MAX, leading to a zero-sized memory allocation and a subsequent heap-based buffer overflow. This can allow an attacker to compromise data integrity or cause a denial of service.

Recommendations For grub2 versions prior to 2.06, consider updating to version 2.06 or later to resolve the issue. As a temporary workaround, restrict the use of symbolic links in ext filesystems to minimize the risk of exploitation.

Exploit

Fix

Integer Overflow

Heap Based Buffer Overflow

Memory Corruption

Weakness Enumeration

CWE-190

CWE-122

CWE-787

Related Identifiers

ALT-PU-2020-3534

ALT-PU-2021-1969

ALT-PU-2021-3464

AZL-6459

BDU:2020-03970

CESA-2020_3216

CESA-2020_3217

CVE-2020-14311

DSA-4735-1

DSA-4735-2

MGASA-2021-0315

OPENSUSE-SU-2020:1168-1

OPENSUSE-SU-2020:1169-1

OPENSUSE-SU-2020_1168-1

OPENSUSE-SU-2020_1169-1

RHSA-2020:3216

RHSA-2020:3217

RHSA-2020:3223

RHSA-2020:3227

RHSA-2020:3271

RHSA-2020:3273

RHSA-2020:3274

RHSA-2020:3275

RHSA-2020:3276

RHSA-2020_3216

RHSA-2020_3217

SUSE-SU-2020:14440-1

SUSE-SU-2020:2073-1

SUSE-SU-2020:2074-1

SUSE-SU-2020:2076-1

SUSE-SU-2020:2077-1

SUSE-SU-2020:2078-1

SUSE-SU-2020:2079-1

USN-4432-1

USN-4432-2

Affected Products

Alt Linux

Centos

Linuxmint

Red Hat

Red Os

Suse

Ubuntu

Grub2

References · 85

• 🔥 https://github.com/kukrimate/CVE-2020-14372 · Exploit
• https://osv.dev/vulnerability/USN-4432-1 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-4992-1 · Vendor Advisory
• http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html · Vendor Advisory
• https://wiki.astralinux.ru/astra-linux-se16-bulletin-20200807SE16MD · Vendor Advisory
• https://osv.dev/vulnerability/USN-4432-2 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2020-14311 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2020-14311 · Vendor Advisory
• https://bdu.fstec.ru/vul/2020-03970 · Security Note
• https://ubuntu.com/security/CVE-2020-14311 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-4432-2 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2020-14311 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2020-14311 · Vendor Advisory
• https://ubuntu.com/security/CVE-2020-15707 · Vendor Advisory
• https://osv.dev/vulnerability/MGASA-2021-0315 · Vendor Advisory