RHEL 7 : shim (RHSA-2024:1959)

high Nessus Plugin ID 193728

Language:

Synopsis

The remote Red Hat host is missing one or more security updates for shim.

Description

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2024:1959 advisory.

The shim package contains a first-stage UEFI boot loader that handles chaining to a trusted full boot loader under secure boot environments.

Security Fix(es):

* shim: RCE in http boot support may lead to Secure Boot bypass (CVE-2023-40547)

* shim: Interger overflow leads to heap buffer overflow in verify_sbat_section on 32-bits systems (CVE-2023-40548)

* shim: Out-of-bounds read printing error messages (CVE-2023-40546)

* shim: Out-of-bounds read in verify_buffer_authenticode() malformed PE file (CVE-2023-40549)

* shim: Out-of-bound read in verify_buffer_sbat() (CVE-2023-40550)

* shim: out of bounds read when parsing MZ binaries (CVE-2023-40551)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

IMPORTANT: The new shim revokes ALL VERSIONS of GRUB2 before grub2-2.02-0.87.el7_9.14. Therefore GRUB2 MUST be updated to the latest version: grub2-2.02-0.87.el7_9.14 BEFORE or SIMULTANEOUSLY with this shim in order for Secure Boot to continue to work. Failure to update GRUB2 will result in an UNBOOTABLE system.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

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 RHEL shim package based on the guidance in RHSA-2024:1959.

Plugin Details

Severity: High

ID: 193728

File Name: redhat-RHSA-2024-1959.nasl

Version: 1.2

Type: local

Agent: unix

Family: Red Hat Local Security Checks

Published: 4/23/2024

Updated: 11/7/2024

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Critical

Score: 9.2

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

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

CVSS Score Source: CVE-2023-40547

CVSS v3

Risk Factor: High

Base Score: 8.3

Temporal Score: 7.2

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

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

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:mokutil, p-cpe:/a:redhat:enterprise_linux:shim-x64, cpe:/o:redhat:enterprise_linux:7, p-cpe:/a:redhat:enterprise_linux:shim, p-cpe:/a:redhat:enterprise_linux:shim-unsigned-x64, p-cpe:/a:redhat:enterprise_linux:shim-unsigned-ia32, p-cpe:/a:redhat:enterprise_linux:shim-ia32, p-cpe:/a:redhat:enterprise_linux:shim-signed

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

Exploit Ease: No known exploits are available

Patch Publication Date: 4/23/2024

Vulnerability Publication Date: 12/11/2023

Reference Information

CVE: CVE-2023-40546, CVE-2023-40547, CVE-2023-40548, CVE-2023-40549, CVE-2023-40550, CVE-2023-40551

CWE: 125, 476, 787

RHSA: 2024:1959

Detections

Analytics