Vulnerabilities > CVE-2023-40547 - Unspecified vulnerability in Redhat Enterprise Linux and Shim

047910
CVSS 8.3 - HIGH
Attack vector
ADJACENT_NETWORK
Attack complexity
HIGH
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
high complexity
redhat

Summary

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.