rhboot shim on 32-bit verify_sbat_section heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in rhboot shim on 32-bit. The affected element is the function verify_sbat_section. The manipulation results in heap-based overflow. This vulnerability was named CVE-2023-40548. There is no available exploit.

Detailsinfo

A vulnerability classified as critical has been found in rhboot shim on 32-bit (unknown version). Affected is the function verify_sbat_section. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). This is going to have an impact on confidentiality, integrity, and availability.

The weakness was presented 01/24/2024. The advisory is shared for download at bugzilla.redhat.com. This vulnerability is traded as CVE-2023-40548 since 08/15/2023. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/01/2025).

The vulnerability scanner Nessus provides a plugin with the ID 215974 (Azure Linux 3.0 Security Update: shim / shim-unsigned-aarch64 / shim-unsigned-x64 (CVE-2023-40548)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (215974) and EUVD (EUVD-2023-45119). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.6

VulDB Base Score: 8.0
VulDB Temp Score: 8.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.4
NVD Vector: 🔍

CNA Base Score: 7.4
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 215974
Nessus Name: Azure Linux 3.0 Security Update: shim / shim-unsigned-aarch64 / shim-unsigned-x64 (CVE-2023-40548)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

08/15/2023 🔍
01/24/2024 +162 days 🔍
01/24/2024 +0 days 🔍
10/01/2025 +616 days 🔍

Sourcesinfo

Advisory: bugzilla.redhat.com
Status: Not defined

CVE: CVE-2023-40548 (🔍)
GCVE (CVE): GCVE-0-2023-40548
GCVE (VulDB): GCVE-100-251928
EUVD: 🔍

Entryinfo

Created: 01/24/2024 09:44
Updated: 10/01/2025 12:37
Changes: 01/24/2024 09:44 (37), 02/17/2024 18:11 (1), 02/17/2024 18:19 (21), 06/11/2024 05:50 (19), 09/18/2024 13:20 (5), 10/01/2024 16:33 (4), 02/11/2025 13:22 (2), 10/01/2025 12:37 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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