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CVE-2023-40548

Shim: interger overflow leads to heap buffer overflow in verify_sbat_section on 32-bits systems

Published: Jan 29, 2024Updated: Jun 26, 2026 Sources: CVE List NVD BDUCWE-190
7.4HIGH
NVD MITRE
EPSS Score
0.4%
Top 64.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

A buffer overflow was found in Shim in the 32-bit system. The overflow happens due to an addition operation involving a user-controlled value parsed from the PE binary being used by Shim. This value is further used for memory allocation operations, leading to a heap-based buffer overflow. This flaw causes memory corruption and can lead to a crash or data integrity issues during the boot phase.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:LAC:HPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:LAttack Vector
Local
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-190CWE-787

Affected Products

Red Hat Inc.
commercial·USaka redhat, Red Hat
shimOn-prem
Operating Systems / linux-distro
Red Hat Enterprise Linux 7On-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.2 Advanced Update SupportOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.2 Telecommunications Update ServiceOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.2 Update Services for SAP SolutionsOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.4 Telecommunications Update ServiceOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 8.4 Update Services for SAP SolutionsOn-premOS
Operating Systems / linux-distro
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
ООО «Ред Софт»
commercial·RUaka red soft
РЕД ОСOn-premOS
Operating Systems / linux-distro
АО «ИВК»
commercial·RUaka ivk
АЛЬТ СП 10On-premOS
Operating Systems / linux-distro
Matthew Garrett
individual-devaka shim
shimEmbedded
Hardware Firmware / bios-uefi
and 8 more affected products View all →

Exploitability

Official Patch Available
Workaround Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://access.redhat.com/errata/RHSA-2024:1834
access.redhat.com
https://access.redhat.com/errata/RHSA-2024:1835
access.redhat.com
https://access.redhat.com/errata/RHSA-2024:1873
access.redhat.com
and 14 more references View all →

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