CVE-2026-89765

Kernel stack disclosure via uninitialized structure padding

Published Sep 11, 2026 · Updated Sep 11, 2026

Information disclosure in Linux allows local users on native sparc64 systems to read kernel stack data through the getitimer() system call. put_itimerval() assigns only named fields in a stack-allocated __kernel_old_itimerval, then copies the entire object without clearing two four-byte padding holes. Any local user able to invoke getitimer() on native sparc64 can recover only incidental bytes present in those padding locations.

CVSS severityUnavailable
Unscored
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Linux allows local users on native sparc64 systems to read kernel stack data through the getitimer() system call. put_itimerval() assigns only named fields in a stack-allocated __kernel_old_itimerval, then copies the entire object without clearing two four-byte padding holes. Any local user able to invoke getitimer() on native sparc64 can recover only incidental bytes present in those padding locations.

The record

CVE
CVE-2026-89765
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1005
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 11, 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=0 <6.12.109
  2. Affected versionversion=0 <6.18.50
  3. Affected versionversion=0 <7.2.4
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <00ef529a5402f41eb1d227916437e237450719f9
  5. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <18c7d85864e554adc8fad1e8d2e9d2cb6c3911c8
  6. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2bf5e8f7c9bf4ad3be343a9a6e3e50a34264d25e
  7. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <4c66719dd1e4023c5e3f7d050f1bbefec3dfbeb4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=0 <6.12.109; version=0 <6.18.50; version=0 <7.2.4; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <00ef529a5402f41eb1d227916437e237450719f9; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <18c7d85864e554adc8fad1e8d2e9d2cb6c3911c8; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <2bf5e8f7c9bf4ad3be343a9a6e3e50a34264d25e; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <4c66719dd1e4023c5e3f7d050f1bbefec3dfbeb4

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.

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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
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1005Data from Local System

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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