VDB-252343 · CVE-2023-40551 · EUVD-2023-45122

shim 3.8.15/8 MZ Binary Format out-of-bounds

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.7	$0-$5k	0.00

Summaryinfo

A vulnerability was found in shim. It has been rated as problematic. This vulnerability affects unknown code of the component MZ Binary Format Handler. This manipulation causes out-of-bounds. This vulnerability appears as CVE-2023-40551. The attack requires local access. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic was found in shim. Affected by this vulnerability is an unknown function of the component MZ Binary Format Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in the MZ binary format in Shim. An out-of-bounds read may occur, leading to a crash or possible exposure of sensitive data during the system's boot phase.

The weakness was presented 01/29/2024. It is possible to read the advisory at access.redhat.com. This vulnerability is known as CVE-2023-40551 since 08/15/2023. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 232680 (Azure Linux 3.0 Security Update: shim (CVE-2023-40551)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 15.8 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (232680) and EUVD (EUVD-2023-45122). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

shim

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 4.2
VulDB Temp Score: 4.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.1
NVD Vector: 🔍

CNA Base Score: 5.1
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 232680
Nessus Name: Azure Linux 3.0 Security Update: shim (CVE-2023-40551)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: shim 15.8

Timelineinfo

08/15/2023 🔍
01/29/2024 +167 days 🔍
01/29/2024 +0 days 🔍
10/01/2025 +611 days 🔍

Sourcesinfo

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2023-40551 (🔍)
GCVE (CVE): GCVE-0-2023-40551
GCVE (VulDB): GCVE-100-252343
EUVD: 🔍

Entryinfo

Created: 01/29/2024 22:53
Updated: 10/01/2025 12:37
Changes: 01/29/2024 22:53 (48), 02/21/2024 18:30 (11), 06/11/2024 06:12 (20), 03/13/2025 17:35 (4), 10/01/2025 12:37 (1)
Complete: 🔍
Cache ID: 216::103