cve/2023/CVE-2023-40547.md

### [CVE-2023-40547](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-40547)
![](https://img.shields.io/static/v1?label=Product&message=Red%20Hat%20Enterprise%20Linux%207&color=blue)
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### 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.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/fkie-cad/nvd-json-data-feeds
- https://github.com/seal-community/patches