CVE-2023-40547

HIGH EPSS 90.9%
Published Jan 25, 20242y ago · Modified Jun 26, 20266d ago
8.3 CVSS 3.1
High
Find Similar
Published Jan 25, 2024 2y ago
Last Modified Jun 26, 2026 6d ago

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.

CVSS Details

Base Score
8.3
Exploitability
1.6
Impact
6.0
Vector string
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack Vector Adjacent
Attack Complexity High
Privileges Required None
User Interaction None
Scope Changed
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
90.9% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 2

CWE-346
CWE-787 Out-of-bounds Write Memory Safety

Affected Products 4

VendorProductVersionRange
redhatshim* <15.8
redhatenterprise_linux7.0any
redhatenterprise_linux8.0any
redhatenterprise_linux9.0any

References 13

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.