CVE-2026-98126Hinoki check available

File-size limit bypass via unchecked zero range

Published Sep 25, 2026 · Updated Sep 25, 2026

Improper size validation in the Linux SMB client allows local users to grow files on CIFS mounts beyond the caller's file-size limit. The smb3_zero_range() path sends an extending FALLOC_FL_ZERO_RANGE request without first calling inode_newsize_ok() to enforce RLIMIT_FSIZE. A local process needs write access to a CIFS-mounted file and must omit FALLOC_FL_KEEP_SIZE; successful use expands that file beyond its configured limit.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Improper size validation in the Linux SMB client allows local users to grow files on CIFS mounts beyond the caller's file-size limit. The smb3_zero_range() path sends an extending FALLOC_FL_ZERO_RANGE request without first calling inode_newsize_ok() to enforce RLIMIT_FSIZE. A local process needs write access to a CIFS-mounted file and must omit FALLOC_FL_KEEP_SIZE; successful use expands that file beyond its configured limit.

The record

CVE
CVE-2026-98126
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 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?

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  1. Affected versionversion=5.1
  2. Affected versionversion=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <06a4f9049cb6dc319bceec2dc813ba89add8b828
  3. Affected versionversion=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <3673f057b64abfa957e8ae84448db69369a5091a
  4. Affected versionversion=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <88972e35750792e717af287dc71f42a03b5cbce4
  5. Affected versionversion=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <f320ca20c273a26cd779bdb2b2e4b076a95c76f6

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=5.1; version=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <06a4f9049cb6dc319bceec2dc813ba89add8b828; version=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <3673f057b64abfa957e8ae84448db69369a5091a; version=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <88972e35750792e717af287dc71f42a03b5cbce4; version=72c419d9b073628d3b5b0b2fc787b724f1a8c726 <f320ca20c273a26cd779bdb2b2e4b076a95c76f6

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.

Activity data is delayed. The latest report is Sep 28, 2026.

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No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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