CVE-2026-45919

CPU hardlockup via repeated scheduler self-IPIs

Published May 27, 2026 · Updated May 27, 2026

Denial of service in the Linux kernel real-time scheduler allows local users to trigger a CPU hardlockup through RT load balancing. In rto_next_cpu(), a loop-generation mismatch restarts the CPU search at -1 and reselects the initiating overloaded CPU, which queues irq_work to itself and repeats self-IPIs indefinitely. The path requires HAVE_RT_PUSH_IPI and a specific multicore workload with one overloaded CPU while other CPUs invoke pull_rt_tasks(); continuous self-interrupts then stop that CPU from making progress.

CVSS severity5.5
Medium
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

Denial of service in the Linux kernel real-time scheduler allows local users to trigger a CPU hardlockup through RT load balancing. In rto_next_cpu(), a loop-generation mismatch restarts the CPU search at -1 and reselects the initiating overloaded CPU, which queues irq_work to itself and repeats self-IPIs indefinitely. The path requires HAVE_RT_PUSH_IPI and a specific multicore workload with one overloaded CPU while other CPUs invoke pull_rt_tasks(); continuous self-interrupts then stop that CPU from making progress.

The record

CVE
CVE-2026-45919
Published
May 27, 2026
Updated
May 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-835, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 27, 2026CVE publishedPublication date reported by the CVE source.
  2. May 27, 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=1c37ff78298a6b6063649123356a312e1cce12ca
  2. Affected versionversion=4.14.3 <4.15
  3. Affected versionversion=4.15
  4. Affected versionversion=4.4.103 <4.5
  5. Affected versionversion=4.9.66 <4.10
  6. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <16ca9f3117e9a294646c897daf08a5ab546c711b
  7. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <3b3c672a66db3de3b40f8a7057864bc1f874ede3
  8. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <52aeb1e07ec223caf212f036817976c98d2aa250
  9. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <8ad5577b2d4acfd83f03d97a0aece2d18aac5f07
  10. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <94894c9c477e53bcea052e075c53f89df3d2a33e
  11. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <9f25edc5a20cb52a5abbf25f0724bb4732b81801
  12. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <a6a73403733e86748421f2eeaf028c85683ef896
  13. Affected versionversion=4bdced5c9a2922521e325896a7bbbf0132c94e56 <d57d0746276a88ea43a2cc62b849fd8a95e32e41
  14. Affected versionversion=cb1831a83e54cd3269a2420fce81c4fd8ae6f667
  15. Affected versionversion=f17c786b28a3060a566a170c2cf3bd7441fc30a3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1c37ff78298a6b6063649123356a312e1cce12ca; version=4.14.3 <4.15; version=4.15; version=4.4.103 <4.5; version=4.9.66 <4.10; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <16ca9f3117e9a294646c897daf08a5ab546c711b; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <3b3c672a66db3de3b40f8a7057864bc1f874ede3; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <52aeb1e07ec223caf212f036817976c98d2aa250; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <8ad5577b2d4acfd83f03d97a0aece2d18aac5f07; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <94894c9c477e53bcea052e075c53f89df3d2a33e; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <9f25edc5a20cb52a5abbf25f0724bb4732b81801; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <a6a73403733e86748421f2eeaf028c85683ef896; version=4bdced5c9a2922521e325896a7bbbf0132c94e56 <d57d0746276a88ea43a2cc62b849fd8a95e32e41; version=cb1831a83e54cd3269a2420fce81c4fd8ae6f667; version=f17c786b28a3060a566a170c2cf3bd7441fc30a3

Published CVSS scores

5.5NIST NVDCVSS: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.

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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

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
T1499.004Application or System Exploitation

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

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Your stack

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