CVE-2023-53506Public exploit

Data exposure and corruption via extent merge arithmetic

Published Oct 1, 2025 · Updated Oct 1, 2025

Filesystem extent corruption in the Linux kernel allows local users to read or corrupt data through writes to a mounted UDF filesystem. udf_merge_extents uses sign-inverted arithmetic when redistributing oversized adjacent extents, carrying length overflow into extent-type bits. The trigger requires local write access to an already mounted read-write UDF filesystem; it can expose other files, corrupt metadata, or crash the kernel.

CVSS severity7.8
High
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Filesystem extent corruption in the Linux kernel allows local users to read or corrupt data through writes to a mounted UDF filesystem. udf_merge_extents uses sign-inverted arithmetic when redistributing oversized adjacent extents, carrying length overflow into extent-type bits. The trigger requires local write access to an already mounted read-write UDF filesystem; it can expose other files, corrupt metadata, or crash the kernel.

The record

CVE
CVE-2023-53506
Published
Oct 1, 2025
Updated
Oct 1, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1565.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 1, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3d20e3b768aff32112bdce8d3219d923ae75f9f1
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <53cafe1d6d8ef9f93318e5bfccc0d24f27d41ced
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5d029799d381a9ee06209a222cae75f04c5d5304
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7a965da79f2d22601f329cbfce588386b0847544
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <965982feb333aefa9256c0fe188b5f1b958aef63
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9a8d602f0723586e668bae7e65c832ceb9bcc8bc
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <adac9ac6d2e04ea0782b91a00ba10706002f3ec4
  8. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d52252a1de4cf96a34f722b0cd8902d8ff78eb57

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3d20e3b768aff32112bdce8d3219d923ae75f9f1; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <53cafe1d6d8ef9f93318e5bfccc0d24f27d41ced; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <5d029799d381a9ee06209a222cae75f04c5d5304; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <7a965da79f2d22601f329cbfce588386b0847544; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <965982feb333aefa9256c0fe188b5f1b958aef63; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9a8d602f0723586e668bae7e65c832ceb9bcc8bc; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <adac9ac6d2e04ea0782b91a00ba10706002f3ec4; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d52252a1de4cf96a34f722b0cd8902d8ff78eb57

Published CVSS scores

7.8LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

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)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1565.001Stored Data Manipulation

Public exploit references

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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