CVE-2026-80820Hinoki check available

Online filesystem scrub hang via circular inode list

Published Sep 4, 2026 · Updated Sep 4, 2026

Denial of service in Linux kernel XFS allows attackers to hang online filesystem scrub via a circular unlinked inode list. The AGI scrub paths follow per-allocation-group unlinked inode chains without recording visited inode numbers, so a cycle repeats indefinitely. The hang requires an XFS filesystem whose AGI unlinked list already contains a cycle and an online scrub that traverses that list; no remote trigger is disclosed.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Denial of service in Linux kernel XFS allows attackers to hang online filesystem scrub via a circular unlinked inode list. The AGI scrub paths follow per-allocation-group unlinked inode chains without recording visited inode numbers, so a cycle repeats indefinitely. The hang requires an XFS filesystem whose AGI unlinked list already contains a cycle and an online scrub that traverses that list; no remote trigger is disclosed.

The record

CVE
CVE-2026-80820
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-400
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 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=4.15
  2. Affected versionversion=a12890aebb895951720ff884eab1c99a30645b29 <159d162fe80bd56573cafde5801bd5a90a3dd1ac
  3. Affected versionversion=a12890aebb895951720ff884eab1c99a30645b29 <527eaaefddb6ec5c83a06c9a1559960dd6361753
  4. Affected versionversion=a12890aebb895951720ff884eab1c99a30645b29 <56407a61a8bb85b884de802d39635abdb0ea7408
  5. Affected versionversion=a12890aebb895951720ff884eab1c99a30645b29 <599453f83458b57995290a1d31200c263e2c2691

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=4.15; version=a12890aebb895951720ff884eab1c99a30645b29 <159d162fe80bd56573cafde5801bd5a90a3dd1ac; version=a12890aebb895951720ff884eab1c99a30645b29 <527eaaefddb6ec5c83a06c9a1559960dd6361753; version=a12890aebb895951720ff884eab1c99a30645b29 <56407a61a8bb85b884de802d39635abdb0ea7408; version=a12890aebb895951720ff884eab1c99a30645b29 <599453f83458b57995290a1d31200c263e2c2691

Published CVSS scores

No CVSS assessment is available in this record.

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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption

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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