Debian DSA-4735-1 : grub2 - security update

high Nessus Plugin ID 139099


The remote Debian host is missing a security-related update.


Several vulnerabilities have been discovered in the GRUB2 bootloader.

- CVE-2020-10713 A flaw in the grub.cfg parsing code was found allowing to break UEFI Secure Boot and load arbitrary code.
Details can be found at e-boot/

- CVE-2020-14308 It was discovered that grub_malloc does not validate the allocation size allowing for arithmetic overflow and subsequently a heap-based buffer overflow.

- CVE-2020-14309 An integer overflow in grub_squash_read_symlink may lead to a heap based buffer overflow.

- CVE-2020-14310 An integer overflow in read_section_from_string may lead to a heap based buffer overflow.

- CVE-2020-14311 An integer overflow in grub_ext2_read_link may lead to a heap-based buffer overflow.

- CVE-2020-15706 script: Avoid a use-after-free when redefining a function during execution.

- CVE-2020-15707 An integer overflow flaw was found in the initrd size handling.

Further detailed information can be found at


Upgrade the grub2 packages.

For the stable distribution (buster), these problems have been fixed in version 2.02+dfsg1-20+deb10u1.

See Also

Plugin Details

Severity: High

ID: 139099

File Name: debian_DSA-4735.nasl

Version: 1.7

Type: local

Agent: unix

Published: 7/30/2020

Updated: 5/13/2022

Supported Sensors: Frictionless Assessment Agent, Nessus Agent

Risk Information


Risk Factor: High

Score: 8.1


Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS Score Source: CVE-2020-14309


Risk Factor: High

Base Score: 8.2

Temporal Score: 7.1

Vector: CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:grub2, cpe:/o:debian:debian_linux:10.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 7/29/2020

Vulnerability Publication Date: 7/29/2020

Reference Information

CVE: CVE-2020-10713, CVE-2020-14308, CVE-2020-14309, CVE-2020-14310, CVE-2020-14311, CVE-2020-15706, CVE-2020-15707

DSA: 4735

IAVA: 2020-A-0349