CVE-2023-40548

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

HIGH 7.4

At a glance

Source: NVD
EPSS: EPSS 0.44 % · percentile 38 (2026-10-28)
State: PUBLISHED
Published: 2024-01-29 14:53 UTC
Updated: 2026-06-26 09:44 UTC
Assigner: redhat
NVD status: Modified

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.

Weaknesses (CWE)

CWE-190 — Integer Overflow or Wraparound
CWE-787 — Out-of-bounds Write

References

Scores

Version	Score	Vector	Scored by
CVSS 3.1	HIGH 7.4	CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	redhat
CVSS 3.1	HIGH 7.4	CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · secalert@redhat.com (Secondary)
CVSS 3.1	HIGH 7.4	CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · nvd@nist.gov (Secondary)

European references

ENISA EUVD · EUVD-2023-45119
GCVE · GCVE-0-2023-40548

CERT-FR advisories

CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2024-AVI-0506 — Multiples vulnérabilités dans Juniper Secure Analytics · cert.ssi.gouv.fr
CERTFR-2024-AVI-0470 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:redhat:shim:*:*:*:*:*:*:*:* < 15.8
cpe:2.3:a:redhat:shim:15.8:rc1:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*

Affected products

Product	Versions
Red Hat · Red Hat Enterprise Linux 7	unaffected 0:15.8-3.el7 < *
Red Hat · Red Hat Enterprise Linux 7	unaffected 0:15.8-1.el7 < *
Red Hat · Red Hat Enterprise Linux 8	unaffected 0:15.8-4.el8_9 < *
Red Hat · Red Hat Enterprise Linux 8.2 Advanced Update Support	unaffected 0:15.8-2.el8_2 < *
Red Hat · Red Hat Enterprise Linux 8.2 Telecommunications Update Service	unaffected 0:15.8-2.el8_2 < *
Red Hat · Red Hat Enterprise Linux 8.2 Update Services for SAP Solutions	unaffected 0:15.8-2.el8_2 < *
Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support	unaffected 0:15.8-2.el8_4 < *
Red Hat · Red Hat Enterprise Linux 8.4 Telecommunications Update Service	unaffected 0:15.8-2.el8_4 < *
Red Hat · Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions	unaffected 0:15.8-2.el8_4 < *
Red Hat · Red Hat Enterprise Linux 8.6 Extended Update Support	unaffected 0:15.8-2.el8_6 < *
Red Hat · Red Hat Enterprise Linux 8.8 Extended Update Support	unaffected 0:15.8-2.el8 < *
Red Hat · Red Hat Enterprise Linux 8.8 Extended Update Support	unaffected 0:15.8-2.el8 < *
Red Hat · Red Hat Enterprise Linux 9	unaffected 0:15.8-4.el9_3 < *
Red Hat · Red Hat Enterprise Linux 9.0 Extended Update Support	unaffected 0:15.8-3.el9 < *
Red Hat · Red Hat Enterprise Linux 9.0 Extended Update Support	unaffected 0:15.8-2.el9 < *
Red Hat · Red Hat Enterprise Linux 9.0 Extended Update Support	unaffected 0:15.8-2.el9 < *
Red Hat · Red Hat Enterprise Linux 9.2 Extended Update Support	unaffected 0:15.8-3.el9_2 < *

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD