CVE-2026-64415

System hang via unpreemptible swap-cluster reclaim

Published Jul 25, 2026 · Updated Jul 25, 2026

Denial of service in Linux Kernel 6.12 allows local users to hang the system by driving sustained memory and swap pressure. swap_reclaim_full_clusters iterates a large full_clusters list without periodic cond_resched() calls, preventing its worker from yielding the CPU. The observed trigger required a heavily loaded 320-CPU arm64 host, many full swap clusters, and about three days of LTP memory/swap stress; no confidentiality or integrity impact is reported.

CVSS severity5.5
Medium
EPSS probability0.09%
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 Linux Kernel 6.12 allows local users to hang the system by driving sustained memory and swap pressure. swap_reclaim_full_clusters iterates a large full_clusters list without periodic cond_resched() calls, preventing its worker from yielding the CPU. The observed trigger required a heavily loaded 320-CPU arm64 host, many full swap clusters, and about three days of LTP memory/swap stress; no confidentiality or integrity impact is reported.

The record

CVE
CVE-2026-64415
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 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=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <2a55fdf9f746a1a6ced7fd62ea1080b8a917e0b0
  2. Affected versionversion=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <60cbe67d1342f34b66df1c2ee328e3cd333767d7
  3. Affected versionversion=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <66366d291f666ddeda5f8c84f253e308de3e6b55
  4. Affected versionversion=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <69c0e6246575b780ae0d3f411c749bcf13c221f3
  5. Affected versionversion=6.12

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <2a55fdf9f746a1a6ced7fd62ea1080b8a917e0b0; version=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <60cbe67d1342f34b66df1c2ee328e3cd333767d7; version=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <66366d291f666ddeda5f8c84f253e308de3e6b55; version=5168a68eb78fa1c67a8b2d31d0642c7fd866cc12 <69c0e6246575b780ae0d3f411c749bcf13c221f3; version=6.12

Published CVSS scores

5.5Amazon LinuxCVSS: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

T1499.004Endpoint Denial of Service: Application or System Exploitation

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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