Description
A remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP request, leading to a completely controlled out-of-bounds write primitive and complete system compromise. This flaw is only exploitable during the early boot phase, an attacker needs to perform a Man-in-the-Middle or compromise the boot server to be able to exploit this vulnerability successfully.
Published: 2024-01-25
Score: 8.3 High
EPSS: 4.2% Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

Vendor Workaround

If a system isn’t required to boot from the network, configure the server’s boot order to disable entirely or skip the network boot.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Debian DLA Debian DLA DLA-3813-1 shim security update
EUVD EUVD EUVD-2023-45118 A remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP request, leading to a completely controlled out-of-bounds write primitive and complete system compromise. This flaw is only exploitable during the early boot phase, an attacker needs to perform a Man-in-the-Middle or compromise the boot server to be able to exploit this vulnerability successfully.
History

Tue, 17 Jun 2025 22:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Fri, 22 Nov 2024 12:00:00 +0000


Mon, 16 Sep 2024 19:45:00 +0000


Subscriptions

Redhat Enterprise Linux Rhel Aus Rhel E4s Rhel Eus Rhel Tus Shim
cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2025-11-20T07:24:31.172Z

Reserved: 2023-08-15T20:04:15.615Z

Link: CVE-2023-40547

cve-icon Vulnrichment

Updated: 2024-08-02T18:38:50.942Z

cve-icon NVD

Status : Modified

Published: 2024-01-25T16:15:07.717

Modified: 2024-11-21T08:19:41.650

Link: CVE-2023-40547

cve-icon Redhat

Severity : Important

Publid Date: 2024-01-23T00:00:00Z

Links: CVE-2023-40547 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses