CVE-2026-64073

Local privilege escalation via irq_work teardown race

Published Jul 19, 2026 · Updated Jul 19, 2026

Use-after-free in affected Linux Kernel releases allows local users to escalate privileges by racing irq_work teardown on PREEMPT_RT. irq_work_single() clears BUSY before its final work dereferences, letting concurrent irq_work_sync() return and free the object prematurely. Low-privileged syscall access and a PREEMPT_RT kernel are required; successful heap reuse grants kernel-memory control or crashes the host.

CVSS severity7.8
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in affected Linux Kernel releases allows local users to escalate privileges by racing irq_work teardown on PREEMPT_RT. irq_work_single() clears BUSY before its final work dereferences, letting concurrent irq_work_sync() return and free the object prematurely. Low-privileged syscall access and a PREEMPT_RT kernel are required; successful heap reuse grants kernel-memory control or crashes the host.

The record

CVE
CVE-2026-64073
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.16
  2. Affected versionversion=810979682ccc98dbd83f341c18a2e556c30a7164 <18c0456ea2615b1a743a6db739c74411c3b42bc6
  3. Affected versionversion=810979682ccc98dbd83f341c18a2e556c30a7164 <2dc79362302922cb18f35e262712b5e58de65442
  4. Affected versionversion=810979682ccc98dbd83f341c18a2e556c30a7164 <684a78183c54c23e70d1cba320f7fc184604210b
  5. Affected versionversion=810979682ccc98dbd83f341c18a2e556c30a7164 <81b582784518196eff1050212a046bc29d3a05dd
  6. Affected versionversion=810979682ccc98dbd83f341c18a2e556c30a7164 <91840be8f710370607f949a627e070896faeddb8
  7. Affected versionversion=810979682ccc98dbd83f341c18a2e556c30a7164 <eef4f71b46a9929ac33e968538c9dd5d96a02460

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=5.16; version=810979682ccc98dbd83f341c18a2e556c30a7164 <18c0456ea2615b1a743a6db739c74411c3b42bc6; version=810979682ccc98dbd83f341c18a2e556c30a7164 <2dc79362302922cb18f35e262712b5e58de65442; version=810979682ccc98dbd83f341c18a2e556c30a7164 <684a78183c54c23e70d1cba320f7fc184604210b; version=810979682ccc98dbd83f341c18a2e556c30a7164 <81b582784518196eff1050212a046bc29d3a05dd; version=810979682ccc98dbd83f341c18a2e556c30a7164 <91840be8f710370607f949a627e070896faeddb8; version=810979682ccc98dbd83f341c18a2e556c30a7164 <eef4f71b46a9929ac33e968538c9dd5d96a02460

Published CVSS scores

7.8LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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