🛡️ CVE-2023-40547
🟠 CVSS 8.3 — High ✅ No Known Exploit CWE-787 NVD
8.3
CVSS Score
0 Low4 Medium7 High9 Critical10

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.

Details

Severity HIGH
CVSS Score 8.3
CVSS Vector CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CWE CWE-787
Public Exploit ✅ No
Source NVD
Published 2024-01-25
Updated 2026-06-08
Modified 2024-11-21
Fix URL N/A

Affected Packages

Software From version Fixed in
enterprise-linux — —
shim — 15.8

References

Issue Tracking, Vendor Advisory https://bugzilla.redhat.com/show_bug.cgi?id=2234589
Issue Tracking, Vendor Advisory https://bugzilla.redhat.com/show_bug.cgi?id=2234589

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