Rocky Linux 8 : grub2, mokutil, shim, and shim-unsigned-x64 (RLSA-2022:5095)

high Nessus Plugin ID 162843

Synopsis

The remote Rocky Linux host is missing one or more security updates.

Description

The remote Rocky Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the RLSA-2022:5095 advisory.

- 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. (CVE-2021-3696)

- A crafted 16-bit grayscale PNG image may lead to a out-of-bounds write in the heap area. An attacker may take advantage of that to cause heap data corruption or eventually arbitrary code execution and circumvent secure boot protections. This issue has a high complexity to be exploited as an attacker needs to perform some triage over the heap layout to achieve signifcant results, also the values written into the memory are repeated three times in a row making difficult to produce valid payloads. This flaw affects grub2 versions prior grub-2.12. (CVE-2021-3695)

- 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. (CVE-2021-3697)

- Integer underflow in grub_net_recv_ip4_packets; A malicious crafted IP packet can lead to an integer underflow in grub_net_recv_ip4_packets() function on rsm->total_len value. Under certain circumstances the total_len value may end up wrapping around to a small integer number which will be used in memory allocation. If the attack succeeds in such way, subsequent operations can write past the end of the buffer. (CVE-2022-28733)

- Out-of-bounds write when handling split HTTP headers; When handling split HTTP headers, GRUB2 HTTP code accidentally moves its internal data buffer point by one position. This can lead to a out-of-bound write further when parsing the HTTP request, writing a NULL byte past the buffer. It's conceivable that an attacker controlled set of packets can lead to corruption of the GRUB2's internal memory metadata.
(CVE-2022-28734)

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.

Plugin Details

Severity: High

ID: 162843

File Name: rocky_linux_RLSA-2022-5095.nasl

Version: 1.8

Type: local

Family: Rocky Linux Local Security Checks

Published: 7/8/2022

Updated: 1/18/2024

Supported Sensors: Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.9

Temporal Score: 5.1

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

CVSS Score Source: CVE-2021-3696

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.1

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

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

CVSS Score Source: CVE-2022-28733

Vulnerability Information

CPE: p-cpe:/a:rocky:linux:grub2-tools-efi, p-cpe:/a:rocky:linux:grub2-efi-ia32-cdboot, p-cpe:/a:rocky:linux:grub2-efi-ia32-modules, p-cpe:/a:rocky:linux:shim-aa64, p-cpe:/a:rocky:linux:grub2-tools-extra-debuginfo, p-cpe:/a:rocky:linux:grub2-debugsource, p-cpe:/a:rocky:linux:grub2-efi-x64, cpe:/o:rocky:linux:8, p-cpe:/a:rocky:linux:grub2-tools-minimal-debuginfo, p-cpe:/a:rocky:linux:grub2-efi-aa64-modules, p-cpe:/a:rocky:linux:grub2-efi-x64-modules, p-cpe:/a:rocky:linux:grub2-tools-minimal, p-cpe:/a:rocky:linux:grub2-efi-aa64, p-cpe:/a:rocky:linux:shim-x64, p-cpe:/a:rocky:linux:grub2-efi-aa64-cdboot, p-cpe:/a:rocky:linux:mokutil-debugsource, p-cpe:/a:rocky:linux:grub2-debuginfo, p-cpe:/a:rocky:linux:grub2-pc, p-cpe:/a:rocky:linux:grub2-pc-modules, p-cpe:/a:rocky:linux:grub2-tools-extra, p-cpe:/a:rocky:linux:grub2-efi-x64-cdboot, p-cpe:/a:rocky:linux:grub2-tools, p-cpe:/a:rocky:linux:grub2-tools-debuginfo, p-cpe:/a:rocky:linux:shim-unsigned-x64, p-cpe:/a:rocky:linux:grub2-common, p-cpe:/a:rocky:linux:grub2-efi-ia32, p-cpe:/a:rocky:linux:shim-ia32, p-cpe:/a:rocky:linux:mokutil, p-cpe:/a:rocky:linux:grub2-tools-efi-debuginfo, p-cpe:/a:rocky:linux:mokutil-debuginfo

Required KB Items: Host/local_checks_enabled, Host/RockyLinux/release, Host/RockyLinux/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 7/7/2022

Vulnerability Publication Date: 6/16/2022

Reference Information

CVE: CVE-2021-3695, CVE-2021-3696, CVE-2021-3697, CVE-2022-28733, CVE-2022-28734, CVE-2022-28735, CVE-2022-28736, CVE-2022-28737

Detections

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