Oracle Linux: CVE-2022-3775: ELSA-2023-0049: grub2 security update (MODERATE) (Multiple Advisories)

When rendering certain unicode sequences, grub2's font code doesn't proper validate if the informed glyph's width and height is constrained within bitmap size. As consequence an attacker can craft an input which will lead to a out-of-bounds write into grub2's heap, leading to memory corruption and availability issues. Although complex, arbitrary code execution could not be discarded.
A flaw was found in the grub2 font code. When rendering certain unicode sequences, it fails to properly validate the font width and height. These values are further used to access the font buffer, causing possible out-of-bounds writes. A malicious actor may craft a font capable of triggering this issue, allowing modifications in unauthorized memory segments, causing data integrity problems or leading to denial of service.