CVE-2026-53326

System hang via hardirq pool allocation deadlock

Published Jul 1, 2026 · Updated Jul 1, 2026

Improper locking in Linux Kernel 6.19 allows local users to hang an ARM64 PREEMPT_RT system during early boot. A hard interrupt can call debugobjects fill_pool() before scheduling starts and enter an allocation path requiring a lock already held by the interrupted code. Exposure requires an ARM64 debug PREEMPT_RT kernel and an interrupt during this early-boot window; the resulting lock cycle deadlocks the kernel.

CVSS severity5.5
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper locking in Linux Kernel 6.19 allows local users to hang an ARM64 PREEMPT_RT system during early boot. A hard interrupt can call debugobjects fill_pool() before scheduling starts and enter an allocation path requiring a lock already held by the interrupted code. Exposure requires an ARM64 debug PREEMPT_RT kernel and an interrupt during this early-boot window; the resulting lock cycle deadlocks the kernel.

The record

CVE
CVE-2026-53326
Published
Jul 1, 2026
Updated
Jul 1, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-667, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

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

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=06e0ae988f6e3499785c407429953ade19c1096b <0d046ae106255cba5eb83b23f78ee93f3620247d
  2. Affected versionversion=06e0ae988f6e3499785c407429953ade19c1096b <7bc71bdb1c1526c7f02a6adab324394ff1327b0a
  3. Affected versionversion=6.19
  4. Affected versionversion=a460935022f512e167b4c5d4c12d85f89ba6aabd <44b8b03a9fb5c575548fc72c674653d6baba142a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=06e0ae988f6e3499785c407429953ade19c1096b <0d046ae106255cba5eb83b23f78ee93f3620247d; version=06e0ae988f6e3499785c407429953ade19c1096b <7bc71bdb1c1526c7f02a6adab324394ff1327b0a; version=6.19; version=a460935022f512e167b4c5d4c12d85f89ba6aabd <44b8b03a9fb5c575548fc72c674653d6baba142a

Published CVSS scores

5.5NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

CWE-667Improper Locking
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo