Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS : GRUB 2 vulnerabilities (USN-4432-1)

high Nessus Plugin ID 139179

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4432-1 advisory.

Jesse Michael and Mickey Shkatov discovered that the configuration parser in GRUB2 did not properly exit when errors were discovered, resulting in heap-based buffer overflows. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-10713)

Chris Coulson discovered that the GRUB2 function handling code did not properly handle a function being redefined, leading to a use-after-free vulnerability. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-15706)

Chris Coulson discovered that multiple integer overflows existed in GRUB2 when handling certain filesystems or font files, leading to heap-based buffer overflows. A local attacker could use these to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-14309, CVE-2020-14310, CVE-2020-14311)

It was discovered that the memory allocator for GRUB2 did not validate allocation size, resulting in multiple integer overflows and heap-based buffer overflows when handling certain filesystems, PNG images or disk metadata. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-14308)

Mathieu Trudel-Lapierre discovered that in certain situations, GRUB2 failed to validate kernel signatures.
A local attacker could use this to bypass Secure Boot restrictions. (CVE-2020-15705)

Colin Watson and Chris Coulson discovered that an integer overflow existed in GRUB2 when handling the initrd command, leading to a heap-based buffer overflow. A local attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. (CVE-2020-15707)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-4432-1

Plugin Details

Severity: High

ID: 139179

File Name: ubuntu_USN-4432-1.nasl

Version: 1.13

Type: local

Agent: unix

Published: 7/30/2020

Updated: 8/27/2024

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2020-14309

CVSS v3

Risk Factor: High

Base Score: 8.2

Temporal Score: 7.4

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

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

CVSS Score Source: CVE-2020-10713

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:grub-firmware-qemu, p-cpe:/a:canonical:ubuntu_linux:grub-efi-arm64-signed-template, p-cpe:/a:canonical:ubuntu_linux:grub-efi-arm64, p-cpe:/a:canonical:ubuntu_linux:grub-xen, p-cpe:/a:canonical:ubuntu_linux:grub-emu, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:grub-ieee1275, p-cpe:/a:canonical:ubuntu_linux:grub-common, p-cpe:/a:canonical:ubuntu_linux:grub-mount-udeb, p-cpe:/a:canonical:ubuntu_linux:grub2, p-cpe:/a:canonical:ubuntu_linux:grub-uboot, p-cpe:/a:canonical:ubuntu_linux:grub-uboot-bin, p-cpe:/a:canonical:ubuntu_linux:grub-xen-host, p-cpe:/a:canonical:ubuntu_linux:grub-coreboot-bin, p-cpe:/a:canonical:ubuntu_linux:grub-efi, p-cpe:/a:canonical:ubuntu_linux:grub-efi-arm, p-cpe:/a:canonical:ubuntu_linux:grub-efi-arm64-bin, p-cpe:/a:canonical:ubuntu_linux:grub-ieee1275-bin, p-cpe:/a:canonical:ubuntu_linux:grub-pc-bin, p-cpe:/a:canonical:ubuntu_linux:grub-efi-arm64-signed, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:grub-linuxbios, p-cpe:/a:canonical:ubuntu_linux:grub-xen-bin, p-cpe:/a:canonical:ubuntu_linux:grub-pc, p-cpe:/a:canonical:ubuntu_linux:grub-theme-starfield, p-cpe:/a:canonical:ubuntu_linux:grub2-common, p-cpe:/a:canonical:ubuntu_linux:grub-rescue-pc, p-cpe:/a:canonical:ubuntu_linux:grub-efi-amd64, p-cpe:/a:canonical:ubuntu_linux:grub-efi-amd64-signed, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:grub-efi-amd64-bin, p-cpe:/a:canonical:ubuntu_linux:grub-efi-amd64-signed-template, p-cpe:/a:canonical:ubuntu_linux:grub-efi-arm-bin, p-cpe:/a:canonical:ubuntu_linux:grub-efi-ia32-bin, p-cpe:/a:canonical:ubuntu_linux:grub-efi-ia32, p-cpe:/a:canonical:ubuntu_linux:grub-coreboot

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

Exploit Available: true

Exploit Ease: 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-2020-15705, CVE-2020-15706, CVE-2020-15707

IAVA: 2020-A-0349

USN: 4432-1