CVE-2025-38579

Data disclosure and kernel panic via uninitialized extents

Published Aug 19, 2025 · Updated Aug 5, 2026

Uninitialized-memory use in the Linux f2fs extent cache allows local users to disclose data, corrupt files, or panic the kernel. get_read_extent_info() initializes only fofs, blk, and len in struct extent_info, so the merge helpers later consume indeterminate union fields. Ordinary file access on a mounted f2fs volume reaches the path without mount privileges or user interaction.

CVSS severity7.8
High
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uninitialized-memory use in the Linux f2fs extent cache allows local users to disclose data, corrupt files, or panic the kernel. get_read_extent_info() initializes only fofs, blk, and len in struct extent_info, so the merge helpers later consume indeterminate union fields. Ordinary file access on a mounted f2fs volume reaches the path without mount privileges or user interaction.

The record

CVE
CVE-2025-38579
Published
Aug 19, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-908, T1005, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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=5.15
  2. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <01b6f5955e0008af6bc3a181310d2744bb349800
  3. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <08e8ab00a6d20d5544c932ee85a297d833895141
  4. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <154467f4ad033473e5c903a03e7b9bca7df9a0fa
  5. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <44a79437309e0ee2276ac17aaedc71253af253a8
  6. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <cc1615d5aba4f396cf412579928539a2b124c8a0
  7. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <dabfa3952c8e6bfe6414dbf32e8b6c5f349dc898
  8. Affected versionversion=94afd6d6e5253179c9b891d02081cc8355a11768 <e68b751ec2b15d866967812c57cfdfc1eba6a269

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.15; version=94afd6d6e5253179c9b891d02081cc8355a11768 <01b6f5955e0008af6bc3a181310d2744bb349800; version=94afd6d6e5253179c9b891d02081cc8355a11768 <08e8ab00a6d20d5544c932ee85a297d833895141; version=94afd6d6e5253179c9b891d02081cc8355a11768 <154467f4ad033473e5c903a03e7b9bca7df9a0fa; version=94afd6d6e5253179c9b891d02081cc8355a11768 <44a79437309e0ee2276ac17aaedc71253af253a8; version=94afd6d6e5253179c9b891d02081cc8355a11768 <cc1615d5aba4f396cf412579928539a2b124c8a0; version=94afd6d6e5253179c9b891d02081cc8355a11768 <dabfa3952c8e6bfe6414dbf32e8b6c5f349dc898; version=94afd6d6e5253179c9b891d02081cc8355a11768 <e68b751ec2b15d866967812c57cfdfc1eba6a269

Published CVSS scores

7.8kernel.orgCVSS: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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-908Use of Uninitialized Resource
T1005Data from Local System
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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