CVE-2026-74723

Kernel crash via malformed inline LZO extent

Published Aug 22, 2026 · Updated Aug 25, 2026

Out-of-bounds read in Linux 2.6.38 through 7.1.8 allows local users to crash the kernel via a crafted btrfs image. In fs/btrfs/lzo.c, lzo_decompress() trusts an inline extent's total-length header and reads a missing segment header past the item boundary. The attacker must cause the system to read an inline LZO-compressed file extent containing a header but no segment header or payload; the documented consequence is a kernel crash and service interruption.

CVSS severity5.5
Medium
EPSS probability0.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in Linux 2.6.38 through 7.1.8 allows local users to crash the kernel via a crafted btrfs image. In fs/btrfs/lzo.c, lzo_decompress() trusts an inline extent's total-length header and reads a missing segment header past the item boundary. The attacker must cause the system to read an inline LZO-compressed file extent containing a header but no segment header or payload; the documented consequence is a kernel crash and service interruption.

The record

CVE
CVE-2026-74723
Published
Aug 22, 2026
Updated
Aug 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-125, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 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=2.6.38
  2. Affected versionversion=a6fa6fae40ec336c7df6155255ae64ebef43a8bc <0fa78ef637deb5dbe341582f88553a4bce496de0
  3. Affected versionversion=a6fa6fae40ec336c7df6155255ae64ebef43a8bc <fc50b475ad27f50b4dcc98fc4c44e8802bc1b248

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.38; version=a6fa6fae40ec336c7df6155255ae64ebef43a8bc <0fa78ef637deb5dbe341582f88553a4bce496de0; version=a6fa6fae40ec336c7df6155255ae64ebef43a8bc <fc50b475ad27f50b4dcc98fc4c44e8802bc1b248

Published CVSS scores

5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
9.8cve.orgCVSS:3.1/AV:N/AC:L/PR:N/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-125Out-of-bounds Read
T1499Endpoint Denial of Service

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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