Rapid7

vulnerability

Ubuntu: USN-6355-1 (CVE-2021-3697): GRUB2 vulnerabilities

Severity
4
CVSS
(AV:L/AC:M/Au:N/C:P/I:P/A:P)
Published
Jul 6, 2022
Added
Sep 18, 2023
Modified
Mar 27, 2026

Description

A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.

Solutions

ubuntu-upgrade-grub-efi-amd64ubuntu-upgrade-grub-efi-amd64-binubuntu-upgrade-grub-efi-amd64-signedubuntu-upgrade-grub-efi-arm64ubuntu-upgrade-grub-efi-arm64-binubuntu-upgrade-grub-efi-arm64-signedubuntu-upgrade-shimubuntu-upgrade-shim-signed
Title
Rapid7 Labs

2026 Global Threat Landscape Report

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