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Full vulnerability report · 2026
CVE-2026-64152High confidence

iommu: Handle unmap error when iommu_debug is enabled

Linux · Linux

7.8HighCVSS 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.

13 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 archivelinux-aws-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-fde-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-azure-nvidia-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-gcp-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-hwe-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatency-hwe-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-nvidia-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oem-6.11Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-oracle-6.14Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Ubuntu 24.04 LTSnoble · standard archivelinux-riscvAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 9 Sept 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-64152 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitykernel: iommu: Handle unmap error when iommu_debug is enabled
76 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • kernel as a component of Red Hat Enterprise Linux 10
  • kernel-64k as a component of Red Hat Enterprise Linux 10
  • kernel-64k-core as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-core as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-devel as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-devel-matched as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-modules as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-modules-core as a component of Red Hat Enterprise Linux 10
  • kernel-64k-debug-modules-extra as a component of Red Hat Enterprise Linux 10
  • kernel-64k-devel as a component of Red Hat Enterprise Linux 10
  • kernel-64k-devel-matched as a component of Red Hat Enterprise Linux 10
Summary
A flaw was found in the Linux kernel's Input/Output Memory Management Unit (IOMMU) subsystem when `iommu_debug` is enabled. This issue occurs because an error handling path attempts to unmap memory without a proper initial mapping, leading to an inconsistent state within the IOMMU's debugging and tracing mechanisms. This malfunction could result in unbalanced tracking, potentially affecting system stability or the accuracy of IOMMU debugging information.
Remediation
To mitigate this issue in Red Hat In-Vehicle OS, ensure that the `iommu_debug` kernel parameter is not enabled. This can typically be achieved by verifying that `iommu_debug` is not present in the kernel command line arguments during boot. Disabling this debug feature may impact diagnostic capabilities but will prevent the vulnerable code path from being exercised. A system reboot is required for changes to kernel boot parameters to take effect.
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-2026-45837

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

In the Linux kernel, the following vulnerability has been resolved: iommu: Handle unmap error when iommu_debug is enabled Sashiko noticed a latent bug where the map error flow called iommu_unmap() which calls iommu_debug_unmap_begin()/iommu_debug_unmap_end() however since this is an error path the map flow never actually established the original iommu_debug_map() it will malfunction. Lift the unmap error handling into iommu_map_nosync() and reorder it so the trace_map()/iommu_debug_map() records the partial mapping and then immediately unmaps it. This avoid creating the unbalanced tracking and provides saner tracing instead of a unmap unmatched to any map.

What

In the Linux kernel, the following vulnerability has been resolved: iommu: Handle unmap error when iommu_debug is enabled Sashiko noticed a latent bug where the map error flow called iommu_unmap() which calls iommu_debug_unmap_begin()/iommu_debug_unmap_end() however since this is an error path the map flow never actually established the original iommu_debug_map() it will malfunction. Lift the unmap error handling into iommu_map_nosync() and reorder it so the trace_map()/iommu_debug_map() records the partial mapping and then immediately unmaps it. This avoid creating the unbalanced tracking and provides saner tracing instead of a unmap unmatched to any map.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

In the Linux kernel, the following vulnerability has been resolved: iommu: Handle unmap error when iommu_debug is enabled Sashiko noticed a latent bug where the map error flow called iommu_unmap() which calls iommu_debug_unmap_begin()/iommu_debug_unmap_end() however since this is an error path the map flow never actually established the original iommu_debug_map() it will malfunction. Lift the unmap error handling into iommu_map_nosync() and reorder it so the trace_map()/iommu_debug_map() records the partial mapping and then immediately unmaps it. This avoid creating the unbalanced tracking and provides saner tracing instead of a unmap unmatched to any map.

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

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 → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Changed: exploitation can affect a different security authority
Weakness
?CWE means Common Weakness Enumeration.
CWE not yet assigned
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:L/UI:N/S:C/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.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security 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.
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2026-2403Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen, möglicherweise Sicherheitsmaßnahmen zu umgehen, einen Denial-of-Service-Zustand herbeizuführen oder vertrauliche Informationen offenzulegen.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-1066Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-64143 Référence CVE CVE-2026-64144 https://www.cve.org/CVERecord?id=CVE-2026-64144 Référence CVE CVE-2026-64145 https://www.cve.org/CVERecord?id=CVE-2026-64145 Référence CVE CVE-2026-64146 https://www.cve.org/CVERecord?id=CVE-2026-64146 Référence CVE CVE-2026-64147 https://www.cve.org/CVERecord?id=CVE-2026-64147 Référence CVE CVE-2026-64148 https://www.cve.org/CVERecord?id=CVE-2026-64148 Référence CVE CVE-2026-64149 https://www.cve.org/CVERecord?id=CVE-2026-64149 Référence CVE CVE-2026-64150 https://www.cve.org/CVERecord?id=CVE-2026-64150 Référence CVE CVE-2026-64151 https://www.cve.org/CVERecord?id=CVE-2026-64151 Référence CVE CVE-2026-64152 https://www.cve.org/CVERecord?id=CVE-2026-64152 Référence CVE CVE-2026-64153 https://www.cve.org/CVERecord?id=CVE-2026-64153 Référence CVE CVE-2026-64154 https://www.cve.org/CVERecord?id=CVE-2026-64154 Référence CVE CVE-2026-64155 https://www.cve.org/CVERecord?id=CVE-2026-64155 Référence CVE CVE-2026-64156 https://www.cve.org/CVERecord?id=CVE-2026-64156 Référence CVE CVE-2026-64157 https://www.cve.org/CVERecord?id=CVE-2026-64157 Référence CVE CVE-2026-64158 https://www.cve.org/CVERecord?id=CVE-2026-64158 Référence CVE CVE-2026-64159 https://www.cve.org/CVERecord?id=CVE-2026-64159 Référence CVE CVE-2026-64160 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0954Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-64143 Référence CVE CVE-2026-64144 https://www.cve.org/CVERecord?id=CVE-2026-64144 Référence CVE CVE-2026-64145 https://www.cve.org/CVERecord?id=CVE-2026-64145 Référence CVE CVE-2026-64146 https://www.cve.org/CVERecord?id=CVE-2026-64146 Référence CVE CVE-2026-64147 https://www.cve.org/CVERecord?id=CVE-2026-64147 Référence CVE CVE-2026-64148 https://www.cve.org/CVERecord?id=CVE-2026-64148 Référence CVE CVE-2026-64149 https://www.cve.org/CVERecord?id=CVE-2026-64149 Référence CVE CVE-2026-64150 https://www.cve.org/CVERecord?id=CVE-2026-64150 Référence CVE CVE-2026-64151 https://www.cve.org/CVERecord?id=CVE-2026-64151 Référence CVE CVE-2026-64152 https://www.cve.org/CVERecord?id=CVE-2026-64152 Référence CVE CVE-2026-64153 https://www.cve.org/CVERecord?id=CVE-2026-64153 Référence CVE CVE-2026-64154 https://www.cve.org/CVERecord?id=CVE-2026-64154 Référence CVE CVE-2026-64155 https://www.cve.org/CVERecord?id=CVE-2026-64155 Référence CVE CVE-2026-64156 https://www.cve.org/CVERecord?id=CVE-2026-64156 Référence CVE CVE-2026-64157 https://www.cve.org/CVERecord?id=CVE-2026-64157 Référence CVE CVE-2026-64158 https://www.cve.org/CVERecord?id=CVE-2026-64158 Référence CVE CVE-2026-64159 https://www.cve.org/CVERecord?id=CVE-2026-64159 Référence CVE CVE-2026-64160 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0926Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2026-64143 Référence CVE CVE-2026-64144 https://www.cve.org/CVERecord?id=CVE-2026-64144 Référence CVE CVE-2026-64145 https://www.cve.org/CVERecord?id=CVE-2026-64145 Référence CVE CVE-2026-64146 https://www.cve.org/CVERecord?id=CVE-2026-64146 Référence CVE CVE-2026-64147 https://www.cve.org/CVERecord?id=CVE-2026-64147 Référence CVE CVE-2026-64148 https://www.cve.org/CVERecord?id=CVE-2026-64148 Référence CVE CVE-2026-64149 https://www.cve.org/CVERecord?id=CVE-2026-64149 Référence CVE CVE-2026-64150 https://www.cve.org/CVERecord?id=CVE-2026-64150 Référence CVE CVE-2026-64151 https://www.cve.org/CVERecord?id=CVE-2026-64151 Référence CVE CVE-2026-64152 https://www.cve.org/CVERecord?id=CVE-2026-64152 Référence CVE CVE-2026-64153 https://www.cve.org/CVERecord?id=CVE-2026-64153 Référence CVE CVE-2026-64154 https://www.cve.org/CVERecord?id=CVE-2026-64154 Référence CVE CVE-2026-64155 https://www.cve.org/CVERecord?id=CVE-2026-64155 Référence CVE CVE-2026-64156 https://www.cve.org/CVERecord?id=CVE-2026-64156 Référence CVE CVE-2026-64157 https://www.cve.org/CVERecord?id=CVE-2026-64157 Référence CVE CVE-2026-64158 https://www.cve.org/CVERecord?id=CVE-2026-64158 Référence CVE CVE-2026-64159 https://www.cve.org/CVERecord?id=CVE-2026-64159 Référence CVE CVE-2026-64160 https://www.cve.org/CVERecord?id=

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
kernel as a component of Red Hat Enterprise Linux 10; kernel-64k as a component of Red Hat Enterprise Linux 10; kernel-64k-core as a component of Red Hat Enterprise Linux 10; kernel-64k-debug as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-core as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-devel as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-modules as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-modules-core as a component of Red Hat Enterprise Linux 10; kernel-64k-debug-modules-extra as a component of Red Hat Enterprise Linux 10; kernel-64k-devel as a component of Red Hat Enterprise Linux 10; kernel-64k-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-64k-modules as a component of Red Hat Enterprise Linux 10; kernel-64k-modules-core as a component of Red Hat Enterprise Linux 10; kernel-64k-modules-extra as a component of Red Hat Enterprise Linux 10; kernel-abi-stablelists as a component of Red Hat Enterprise Linux 10; kernel-core as a component of Red Hat Enterprise Linux 10; kernel-debug as a component of Red Hat Enterprise Linux 10; kernel-debug-core as a component of Red Hat Enterprise Linux 10; kernel-debug-devel as a component of Red Hat Enterprise Linux 10; kernel-debug-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-debug-modules as a component of Red Hat Enterprise Linux 10; kernel-debug-modules-core as a component of Red Hat Enterprise Linux 10; kernel-debug-modules-extra as a component of Red Hat Enterprise Linux 10; kernel-debug-uki-virt as a component of Red Hat Enterprise Linux 10; kernel-devel as a component of Red Hat Enterprise Linux 10; kernel-devel-matched as a component of Red Hat Enterprise Linux 10; kernel-doc as a component of Red Hat Enterprise Linux 10; kernel-modules as a component of Red Hat Enterprise Linux 10; kernel-modules-core as a component of Red Hat Enterprise Linux 10; and 46 more
Fixed
< 7.0; 7.0.11 ≤ 7.0.*; 7.1 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
To mitigate this issue in Red Hat In-Vehicle OS, ensure that the `iommu_debug` kernel parameter is not enabled. This can typically be achieved by verifying that `iommu_debug` is not present in the kernel command line arguments during boot. Disabling this debug feature may impact diagnostic capabilities but will prevent the vulnerable code path from being exercised. A system reboot is required for changes to kernel boot parameters to take effect.
04

Evidence and provenance

Published 19 Jul 2026 · Last source change 5 Aug 2026, 12:39 UTC · CWE not yet assigned

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-2026-45837
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceUnavailable
NVD statusNVD enriched

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

Material change intelligence

What changed after publication

View recent updates →
  1. Vendor guidanceAuthoritative vendor guidance changed from authoritative remediation link to authoritative remediation link · patch.
    Before
    authoritative remediation link
    After
    authoritative remediation link · patch
    416baaa9-dc9f-4396-8d5f-8c081fb06d67 ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2026-45837↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference↗Patch or update reference↗Official CVE record (CNA and ADP data)↗NVD record↗
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-2026-64152 · cve.blacktree.nl