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Full vulnerability report · 2024
CVE-2023-40548High confidence

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

Red Hat · Red Hat Enterprise Linux 7

7.4HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

2 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archiveshimVendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.15.8-0ubuntu1Canonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · standard archiveshim-signedVendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.1.58Canonical record ↗Source updated 10 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2023-45119

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

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.

What

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.

Why

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

How

An attacker operating through local access may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

What

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.

Why

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

How

An attacker operating through local access may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → Integer Overflow or Wraparound → disrupt the affected service
Attack surface
Local
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-190

CWE-190: Integer Overflow or Wraparound. The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
UnauthenticatedDenial of serviceCWE-190
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2024-2100IBM Power Hardware Management Console: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in IBM Power Hardware Management Console ausnutzen, um beliebigen Programmcode auszuführen, einen Denial-of-Service-Zustand zu erzeugen und vertrauliche Informationen preiszugeben.

Official advisory
BSI · German · WID-SEC-W-2024-1313IBM QRadar SIEM: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM ausnutzen, um Dateien zu manipulieren, um einen Denial-of-Service-Zustand erzuegen, um vertrauliche Informationen offenzulegen, um die Sicherheitsmaßnahmen zu umgehen und beliebigen Code auszuführen.

Official advisory
BSI · German · WID-SEC-W-2024-0903Red Hat Enterprise Linux (shim): Mehrere Schwachstellen

Ein lokaler Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux in "shim" ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen, vertrauliche Informationen offenzulegen oder beliebigen Code auszuführen.

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0506Multiples vulnérabilités dans Juniper Secure Analytics

d?id=CVE-2023-39189 Référence CVE CVE-2023-39192 https://www.cve.org/CVERecord?id=CVE-2023-39192 Référence CVE CVE-2023-39193 https://www.cve.org/CVERecord?id=CVE-2023-39193 Référence CVE CVE-2023-39194 https://www.cve.org/CVERecord?id=CVE-2023-39194 Référence CVE CVE-2023-39198 https://www.cve.org/CVERecord?id=CVE-2023-39198 Référence CVE CVE-2023-39615 https://www.cve.org/CVERecord?id=CVE-2023-39615 Référence CVE CVE-2023-40283 https://www.cve.org/CVERecord?id=CVE-2023-40283 Référence CVE CVE-2023-40546 https://www.cve.org/CVERecord?id=CVE-2023-40546 Référence CVE CVE-2023-40547 https://www.cve.org/CVERecord?id=CVE-2023-40547 Référence CVE CVE-2023-40548 https://www.cve.org/CVERecord?id=CVE-2023-40548 Référence CVE CVE-2023-40549 https://www.cve.org/CVERecord?id=CVE-2023-40549 Référence CVE CVE-2023-40550 https://www.cve.org/CVERecord?id=CVE-2023-40550 Référence CVE CVE-2023-40551 https://www.cve.org/CVERecord?id=CVE-2023-40551 Référence CVE CVE-2023-4091 https://www.cve.org/CVERecord?id=CVE-2023-4091 Référence CVE CVE-2023-4128 https://www.cve.org/CVERecord?id=CVE-2023-4128 Référence CVE CVE-2023-4132 https://www.cve.org/CVERecord?id=CVE-2023-4132 Référence CVE CVE-2023-4133 https://www.cve.org/CVERecord?id=CVE-2023-4133 Référence CVE CVE-2023-4155 https://www.cve.org/CVERecord?id=CVE-2023-

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0470Multiples vulnérabilités dans les produits IBM

04 juin 2024 https://www.ibm.com/support/pages/node/7156443 Bulletin de sécurité IBM 7156525 du 05 juin 2024 https://www.ibm.com/support/pages/node/7156525 Bulletin de sécurité IBM 7156667 du 06 juin 2024 https://www.ibm.com/support/pages/node/7156667 Référence CVE CVE-2023-33850 https://www.cve.org/CVERecord?id=CVE-2023-33850 Référence CVE CVE-2023-3758 https://www.cve.org/CVERecord?id=CVE-2023-3758 Référence CVE CVE-2023-38264 https://www.cve.org/CVERecord?id=CVE-2023-38264 Référence CVE CVE-2023-40546 https://www.cve.org/CVERecord?id=CVE-2023-40546 Référence CVE CVE-2023-40547 https://www.cve.org/CVERecord?id=CVE-2023-40547 Référence CVE CVE-2023-40548 https://www.cve.org/CVERecord?id=CVE-2023-40548 Référence CVE CVE-2023-40549 https://www.cve.org/CVERecord?id=CVE-2023-40549 Référence CVE CVE-2023-40550 https://www.cve.org/CVERecord?id=CVE-2023-40550 Référence CVE CVE-2023-40551 https://www.cve.org/CVERecord?id=CVE-2023-40551 Référence CVE CVE-2023-4408 https://www.cve.org/CVERecord?id=CVE-2023-4408 Référence CVE CVE-2023-50387 https://www.cve.org/CVERecord?id=CVE-2023-50387 Référence CVE CVE-2023-50868 https://www.cve.org/CVERecord?id=CVE-2023-50868 Référence CVE CVE-2023-5517 https://www.cve.org/CVERecord?id=CVE-2023-5517 Référence CVE CVE-2023-5679 https://www.cve.org/CVERecord?id=CVE-2

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
See the vendor and CVE records for the affected range.
Fixed
0:15.8-3.el7 < *; 0:15.8-1.el7 < *; 0:15.8-4.el8_9 < *; 0:15.8-2.el8_2 < *; 0:15.8-2.el8_4 < *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 29 Jan 2024 · Last source change 26 Jun 2026, 09:44 UTC · CWE-190 · Integer Overflow or Wraparound

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2023-45119
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment

Missing structured fields: affected versions. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2023-40548 · cve.blacktree.nl