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Full vulnerability report · 2026
CVE-2026-64430High confidence

NTB: epf: Avoid calling pci_irq_vector() from hardirq context

Linux · Linux

7.5HighCVSS 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.

20 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 archivelinuxAffected, 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-awsAffected, 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-azureAffected, 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-fdeAffected, 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-nvidiaAffected, 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-gcpAffected, 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-gkeAffected, 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-gkeopAffected, 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-ibmAffected, 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-lowlatencyAffected, 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-nvidiaAffected, 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-lowlatencyAffected, 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-tegraAffected, 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-oracleAffected, 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-raspiAffected, 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
Ubuntu 24.04 LTSnoble · standard archivelinux-xilinxAffected, 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
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-2026-48774

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: NTB: epf: Avoid calling pci_irq_vector() from hardirq context ntb_epf_vec_isr() calls pci_irq_vector() in hardirq context to derive the vector number. pci_irq_vector() calls msi_get_virq() that takes a mutex and can therefore trigger "scheduling while atomic" splats: BUG: scheduling while atomic: kworker/u33:0/55/0x00010001 ... Call trace: ... schedule+0x38/0x110 schedule_preempt_disabled+0x28/0x50 __mutex_lock.constprop.0+0x848/0x908 __mutex_lock_slowpath+0x18/0x30 mutex_lock+0x4c/0x60 msi_domain_get_virq+0xe8/0x138 pci_irq_vector+0x2c/0x60 ntb_epf_vec_isr+0x28/0x120 [ntb_hw_epf] __handle_irq_event_percpu+0x70/0x3a8 handle_irq_event+0x48/0x100 handle_edge_irq+0x100/0x1c8 ... Cache the Linux IRQ number for vector 0 when vectors are allocated and use it as a base in the ISR. Running the ISR in a threaded IRQ handler would also avoid the problem, but that would be unnecessary here.

What

In the Linux kernel, the following vulnerability has been resolved: NTB: epf: Avoid calling pci_irq_vector() from hardirq context ntb_epf_vec_isr() calls pci_irq_vector() in hardirq context to derive the vector number. pci_irq_vector() calls msi_get_virq() that takes a mutex and can therefore trigger "scheduling while atomic" splats: BUG: scheduling while atomic: kworker/u33:0/55/0x00010001 ... Call trace: ... schedule+0x38/0x110 schedule_preempt_disabled+0x28/0x50 __mutex_lock.constprop.0+0x848/0x908 __mutex_lock_slowpath+0x18/0x30 mutex_lock+0x4c/0x60 msi_domain_get_virq+0xe8/0x138 pci_irq_vector+0x2c/0x60 ntb_epf_vec_isr+0x28/0x120 [ntb_hw_epf] __handle_irq_event_percpu+0x70/0x3a8 handle_irq_event+0x48/0x100 handle_edge_irq+0x100/0x1c8 ... Cache the Linux IRQ number for vector 0 when vectors are allocated and use it as a base in the ISR. Running the ISR in a threaded IRQ handler would also avoid the problem, but that would be unnecessary here.

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 a network path may attempt exploitation without authentication or user interaction. 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: NTB: epf: Avoid calling pci_irq_vector() from hardirq context ntb_epf_vec_isr() calls pci_irq_vector() in hardirq context to derive the vector number. pci_irq_vector() calls msi_get_virq() that takes a mutex and can therefore trigger "scheduling while atomic" splats: BUG: scheduling while atomic: kworker/u33:0/55/0x00010001 ... Call trace: ... schedule+0x38/0x110 schedule_preempt_disabled+0x28/0x50 __mutex_lock.constprop.0+0x848/0x908 __mutex_lock_slowpath+0x18/0x30 mutex_lock+0x4c/0x60 msi_domain_get_virq+0xe8/0x138 pci_irq_vector+0x2c/0x60 ntb_epf_vec_isr+0x28/0x120 [ntb_hw_epf] __handle_irq_event_percpu+0x70/0x3a8 handle_irq_event+0x48/0x100 handle_edge_irq+0x100/0x1c8 ... Cache the Linux IRQ number for vector 0 when vectors are allocated and use it as a base in the ISR. Running the ISR in a threaded IRQ handler would also avoid the problem, but that would be unnecessary here.

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 a network path may attempt exploitation without authentication or user interaction. 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
a network path → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's 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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.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.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticated
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2026-2527Linux Kernel: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um nicht näher spezifizierte Angriffe durchzuführen, dazu können DoS-Angriffe, die Offenlegung von Informationen, die Beschädigung des Speichers oder die Umgehung von Sicherheitsmaßnahmen gehören.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-1031Multiples vulnérabilités dans le noyau Linux de Debian LTS

d?id=CVE-2026-64419 Référence CVE CVE-2026-64420 https://www.cve.org/CVERecord?id=CVE-2026-64420 Référence CVE CVE-2026-64421 https://www.cve.org/CVERecord?id=CVE-2026-64421 Référence CVE CVE-2026-64422 https://www.cve.org/CVERecord?id=CVE-2026-64422 Référence CVE CVE-2026-64423 https://www.cve.org/CVERecord?id=CVE-2026-64423 Référence CVE CVE-2026-64424 https://www.cve.org/CVERecord?id=CVE-2026-64424 Référence CVE CVE-2026-64425 https://www.cve.org/CVERecord?id=CVE-2026-64425 Référence CVE CVE-2026-64428 https://www.cve.org/CVERecord?id=CVE-2026-64428 Référence CVE CVE-2026-64429 https://www.cve.org/CVERecord?id=CVE-2026-64429 Référence CVE CVE-2026-64430 https://www.cve.org/CVERecord?id=CVE-2026-64430 Référence CVE CVE-2026-64432 https://www.cve.org/CVERecord?id=CVE-2026-64432 Référence CVE CVE-2026-64433 https://www.cve.org/CVERecord?id=CVE-2026-64433 Référence CVE CVE-2026-64434 https://www.cve.org/CVERecord?id=CVE-2026-64434 Référence CVE CVE-2026-64435 https://www.cve.org/CVERecord?id=CVE-2026-64435 Référence CVE CVE-2026-64436 https://www.cve.org/CVERecord?id=CVE-2026-64436 Référence CVE CVE-2026-64437 https://www.cve.org/CVERecord?id=CVE-2026-64437 Référence CVE CVE-2026-64438 https://www.cve.org/CVERecord?id=CVE-2026-64438 Référence CVE CVE-2026-64440 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0982Multiples vulnérabilités dans le noyau Linux de Debian LTS

d?id=CVE-2026-64413 Référence CVE CVE-2026-64417 https://www.cve.org/CVERecord?id=CVE-2026-64417 Référence CVE CVE-2026-64419 https://www.cve.org/CVERecord?id=CVE-2026-64419 Référence CVE CVE-2026-64420 https://www.cve.org/CVERecord?id=CVE-2026-64420 Référence CVE CVE-2026-64422 https://www.cve.org/CVERecord?id=CVE-2026-64422 Référence CVE CVE-2026-64423 https://www.cve.org/CVERecord?id=CVE-2026-64423 Référence CVE CVE-2026-64425 https://www.cve.org/CVERecord?id=CVE-2026-64425 Référence CVE CVE-2026-64428 https://www.cve.org/CVERecord?id=CVE-2026-64428 Référence CVE CVE-2026-64429 https://www.cve.org/CVERecord?id=CVE-2026-64429 Référence CVE CVE-2026-64430 https://www.cve.org/CVERecord?id=CVE-2026-64430 Référence CVE CVE-2026-64432 https://www.cve.org/CVERecord?id=CVE-2026-64432 Référence CVE CVE-2026-64435 https://www.cve.org/CVERecord?id=CVE-2026-64435 Référence CVE CVE-2026-64436 https://www.cve.org/CVERecord?id=CVE-2026-64436 Référence CVE CVE-2026-64437 https://www.cve.org/CVERecord?id=CVE-2026-64437 Référence CVE CVE-2026-64438 https://www.cve.org/CVERecord?id=CVE-2026-64438 Référence CVE CVE-2026-64440 https://www.cve.org/CVERecord?id=CVE-2026-64440 Référence CVE CVE-2026-64441 https://www.cve.org/CVERecord?id=CVE-2026-64441 Référence CVE CVE-2026-64442 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
812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 33bba331a4a5fee8b6026fe72eca13cceeec1b7b; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < aff271b12a1eb8c8b3da19223ae1a6abe1e8168b; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 1dba8444ac0100133d72374634f6d7451fff1ccc; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 174a97f21bf9c54fa37ec0f321692e862ea130a3; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < f71e8d9875069fa73e335f63f02ec6e52e3aaa51; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 6350df503897d57c5634f71b0767d48c3b837583; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f; 5.12
Fixed
< 5.12; 5.15.212 ≤ 5.15.*; 6.1.178 ≤ 6.1.*; 6.6.145 ≤ 6.6.*; 6.12.96 ≤ 6.12.*; 6.18.39 ≤ 6.18.*; 7.1.4 ≤ 7.1.*; 7.2 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 25 Jul 2026 · Last source change 17 Aug 2026, 04:55 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-2026-48774
Product sourceCNA
Remediation sourceCVE/CNA references
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
  2. Affected versionsThe structured affected or fixed version information changed.
    Before
    812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 33bba331a4a5fee8b6026fe72eca13cceeec1b7b; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < aff271b12a1eb8c8b3da19223ae1a6abe1e8168b; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 1dba8444ac0100133d72374634f6d7451fff1ccc; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 174a97f21bf9c54fa37ec0f321692e862ea130a3; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < f71e8d9875069fa73e335f63f02ec6e52e3aaa51; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 6350df503897d57c5634f71b0767d48c3b837583; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f; 5.12 · Fixed: < 5.12; 5.15.212 ≤ 5.15.*; 6.1.178 ≤ 6.1.*; 6.6.145 ≤ 6.6.*; 6.12.96 ≤ 6.12.*; 6.18.39 ≤ 6.18.*; 7.1.4 ≤ 7.1.*; 7.2-rc1 ≤ *
    After
    812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 33bba331a4a5fee8b6026fe72eca13cceeec1b7b; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < aff271b12a1eb8c8b3da19223ae1a6abe1e8168b; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 1dba8444ac0100133d72374634f6d7451fff1ccc; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 174a97f21bf9c54fa37ec0f321692e862ea130a3; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < f71e8d9875069fa73e335f63f02ec6e52e3aaa51; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 6350df503897d57c5634f71b0767d48c3b837583; 812ce2f8d14ea791edd88c36ebcc9017bf4c88cb < 4dcddc1c794d1c65eda68f1f8dd04a0fecc0870f; 5.12 · Fixed: < 5.12; 5.15.212 ≤ 5.15.*; 6.1.178 ≤ 6.1.*; 6.6.145 ≤ 6.6.*; 6.12.96 ≤ 6.12.*; 6.18.39 ≤ 6.18.*; 7.1.4 ≤ 7.1.*; 7.2 ≤ *
    CNA
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-2026-64430 · cve.blacktree.nl