It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2023-020 advisory.

    A flaw was found in grub 2, where a crafted 16-bit grayscale PNG image may lead to an out-of-bounds write.
    This flaw allows an attacker to corrupt the data on the heap portion of the grub2's memory, leading to     possible code execution and the circumvention of the secure boot mechanism. (CVE-2021-3695)

    A flaw was found in grub2 when handling a PNG image header. When decoding the data contained in the     Huffman table at the PNG file header, an out-of-bounds write may happen on grub's heap. (CVE-2021-3696)

    A flaw was found in grub2 when handling JPEG images. This flaw allows an attacker to craft a malicious     JPEG image, which leads to an underflow on a grub2's internal pointer, leading to a heap-based out-of-     bounds write. Secure-boot mechanisms circumvention and arbitrary code execution may also be achievable.
    (CVE-2021-3697)

    A flaw in grub2 was found where its configuration file, known as grub.cfg, is being created with the wrong     permission set allowing non privileged users to read its content. This represents a low severity     confidentiality issue, as those users can eventually read any encrypted passwords present in grub.cfg.
    (CVE-2021-3981)

    A flaw was found where a maliciously crafted pf2 font could lead to an out-of-bounds write in grub2. A     successful attack can lead to memory corruption and secure boot circumvention. (CVE-2022-2601)

    A flaw was found in grub2 when handling IPv4 packets. This flaw allows an attacker to craft a malicious     packet, triggering an integer underflow in grub code. Consequently, the memory allocation for handling the     packet data may be smaller than the size needed. This issue causes an out-of-bands write during packet     handling, compromising data integrity, confidentiality issues, a denial of service, and remote code     execution. (CVE-2022-28733)

    A flaw was found in grub2 when handling split HTTP headers. While processing a split HTTP header, grub2     wrongly advances its control pointer to the internal buffer by one position, which can lead to an out-of-     bounds write. This flaw allows an attacker to leverage this issue by crafting a malicious set of HTTP     packages making grub2 corrupt its internal memory metadata structure. This leads to data integrity and     confidentiality issues or forces grub to crash, resulting in a denial of service attack. (CVE-2022-28734)

    A flaw was found in grub2. The shim_lock verifier from grub2 allows non-kernel files to be loaded when     secure boot is enabled, giving the possibility of unverified code or modules to be loaded when it should     not be allowed. (CVE-2022-28735)

    A use-after-free vulnerability was found on grub2's chainloader command. This flaw allows an attacker to     gain access to restricted data or cause arbitrary code execution if they can establish control from grub's     memory allocation pattern. (CVE-2022-28736)

    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. (CVE-2022-3775)

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

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

Detections

Analytics

Amazon Linux 2023 : grub2-common, grub2-efi-aa64, grub2-efi-aa64-cdboot (ALAS2023-2023-020)

high Nessus Plugin ID 173192

Version 1.4

Version 1.3

Version 1.2

Version 1.1

Version 1.0

Version 1.4 Dec 12, 2024, 9:55 AM CVSS metrics ("Cvssv4 score" set to 0.0) CVSSv2 severity (based on None, severity decreased from "High" to "Low") Detection (updated detection logic) Plugin metadata Plugin Feed: 202412120955
Version 1.3 Jan 17, 2024, 2:38 PM CVSS metrics ("CVSSv3 score" set to 8.6. "CVSSv3 vector" set to "CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H") CVSSv3 score source (changed from "CVE-2022-28734" to "CVE-2022-2601") Plugin Feed: 202401171438
Version 1.2 Jul 31, 2023, 2:04 PM CVSS metrics ("CVSSv3 score" changed from 8.6 to 9.8. "CVSSv3 vector" changed from "CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H" to "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H") CVSSv3 score source (changed from "CVE-2022-2601" to "CVE-2022-28734") Plugin Feed: 202307311404
Version 1.1 May 25, 2023, 3:03 PM CVSS temporal metrics ("CVSSv2 temporal vector" set to "CVSS2#E:POC/RL:OF/RC:C". "CVSSv3 temporal vector" set to "CVSS:3.0/E:P/RL:O/RC:C") Exploit attributes ("Exploit available" set to "True". "Exploitability ease" changed from "No known exploits are available" to "Exploits are available") Plugin Feed: 202305251503
Version 1.0 Mar 22, 2023, 12:14 AM New Plugin Feed: 202303220014