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vulnerability

Amazon Linux AMI 2: CVE-2021-3696: Security patch for grub2 (Multiple Advisories)

Severity
7
CVSS
(AV:L/AC:M/Au:N/C:C/I:C/A:C)
Published
Jul 6, 2022
Added
Jul 21, 2023
Modified
May 20, 2026

Description

A heap out-of-bounds write may heppen during the handling of Huffman tables in the PNG reader. This may lead to data corruption in the heap space. Confidentiality, Integrity and Availablity impact may be considered Low as it's very complex to an attacker control the encoding and positioning of corrupted Huffman entries to achieve results such as arbitrary code execution and/or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.

Solutions

amazon-linux-ami-2-upgrade-grub2amazon-linux-ami-2-upgrade-grub2-commonamazon-linux-ami-2-upgrade-grub2-debuginfoamazon-linux-ami-2-upgrade-grub2-efi-aa64amazon-linux-ami-2-upgrade-grub2-efi-aa64-cdbootamazon-linux-ami-2-upgrade-grub2-efi-aa64-ec2amazon-linux-ami-2-upgrade-grub2-efi-aa64-modulesamazon-linux-ami-2-upgrade-grub2-efi-x64amazon-linux-ami-2-upgrade-grub2-efi-x64-cdbootamazon-linux-ami-2-upgrade-grub2-efi-x64-ec2amazon-linux-ami-2-upgrade-grub2-efi-x64-modulesamazon-linux-ami-2-upgrade-grub2-emuamazon-linux-ami-2-upgrade-grub2-emu-modulesamazon-linux-ami-2-upgrade-grub2-pcamazon-linux-ami-2-upgrade-grub2-pc-modulesamazon-linux-ami-2-upgrade-grub2-toolsamazon-linux-ami-2-upgrade-grub2-tools-efiamazon-linux-ami-2-upgrade-grub2-tools-extraamazon-linux-ami-2-upgrade-grub2-tools-minimal
Title
Rapid7 Labs

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