CVE-2026-80720Hinoki check available

Filesystem I/O hang via exhausted shared bioset

Published Aug 28, 2026 · Updated Aug 28, 2026

Deadlock in the iomap I/O completion path in Linux 6.15 allows attackers to hang filesystem I/O through repeated bio splitting. iomap_split_ioend passes bios already allocated from iomap_ioend_bioset back to bio_split using that same finite bioset, so exhaustion prevents allocation progress. Reachability requires I/O that invokes this nested split path; the bounded consequence is an I/O deadlock rather than data disclosure or code execution.

CVSS severityUnavailable
Unscored
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Deadlock in the iomap I/O completion path in Linux 6.15 allows attackers to hang filesystem I/O through repeated bio splitting. iomap_split_ioend passes bios already allocated from iomap_ioend_bioset back to bio_split using that same finite bioset, so exhaustion prevents allocation progress. Reachability requires I/O that invokes this nested split path; the bounded consequence is an I/O deadlock rather than data disclosure or code execution.

The record

CVE
CVE-2026-80720
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 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?

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  1. Affected versionversion=5fcbd555d48390a8c819ba7fdf55fbfcabe05c80 <4a869be56e9f6ce7462abcf324ebdefc5de051be
  2. Affected versionversion=5fcbd555d48390a8c819ba7fdf55fbfcabe05c80 <c679ce3be6cb63763d68ab9b5d9d73ddc0a40762
  3. Affected versionversion=5fcbd555d48390a8c819ba7fdf55fbfcabe05c80 <cfc686a1174aa904dcad9b9a7c5e46b484d27e4e
  4. Affected versionversion=6.15

What conditions does exploitation require?

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

What is affected?

The Linux Kernel Organization · Linuxversion=5fcbd555d48390a8c819ba7fdf55fbfcabe05c80 <4a869be56e9f6ce7462abcf324ebdefc5de051be; version=5fcbd555d48390a8c819ba7fdf55fbfcabe05c80 <c679ce3be6cb63763d68ab9b5d9d73ddc0a40762; version=5fcbd555d48390a8c819ba7fdf55fbfcabe05c80 <cfc686a1174aa904dcad9b9a7c5e46b484d27e4e; version=6.15

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.

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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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

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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