CVE-2023-53247

Kernel crash via stale Btrfs subpage state

Published Sep 15, 2025 · Updated Sep 15, 2025

Reachable assertion in Linux 5.12 through 6.1.41 and 6.2 through 6.4.6 allows local users to crash the kernel via Btrfs writes. In btrfs_cont_expand, release_folio can clear a page's private subpage state after read_folio but before relocking, yet later code modifies the cleared subpage bits and triggers btrfs_subpage_assert. A local user must exercise copy_file_range against a Btrfs filesystem using subpage block sizes; the demonstrated result is a kernel panic and host service interruption.

CVSS severity5.5
Medium
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in Linux 5.12 through 6.1.41 and 6.2 through 6.4.6 allows local users to crash the kernel via Btrfs writes. In btrfs_cont_expand, release_folio can clear a page's private subpage state after read_folio but before relocking, yet later code modifies the cleared subpage bits and triggers btrfs_subpage_assert. A local user must exercise copy_file_range against a Btrfs filesystem using subpage block sizes; the demonstrated result is a kernel panic and host service interruption.

The record

CVE
CVE-2023-53247
Published
Sep 15, 2025
Updated
Sep 15, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-617, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2025Record 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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0a5e0bc8e8618e32a6ca64450867628eb0a627bf
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <17b17fcd6d446b95904a6929c40012ee7f0afc0c
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a5880e69cf7fe4a0bb1eabae02205352d1b59b7b

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <0a5e0bc8e8618e32a6ca64450867628eb0a627bf; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <17b17fcd6d446b95904a6929c40012ee7f0afc0c; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a5880e69cf7fe4a0bb1eabae02205352d1b59b7b

Published CVSS scores

5.5CISA-ADPCVSS: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-617Reachable Assertion
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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