CVE-2026-89761Hinoki check available

Kernel memory corruption via undersized label vector

Published Sep 11, 2026 · Updated Sep 11, 2026

Out-of-bounds write in Linux AppArmor allows local users to corrupt kernel memory through a crafted multi-component label name. aa_label_strn_parse() allocates exactly len vector slots, then aa_vec_unique() writes a NULL terminator at vec[len] when no duplicate components are removed. Exploitation requires AppArmor policy to be loaded; unprivileged local users can reach parsing before permission checks through self-attribute writes or the world-writable securityfs access interface.

CVSS severityUnavailable
Unscored
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Out-of-bounds write in Linux AppArmor allows local users to corrupt kernel memory through a crafted multi-component label name. aa_label_strn_parse() allocates exactly len vector slots, then aa_vec_unique() writes a NULL terminator at vec[len] when no duplicate components are removed. Exploitation requires AppArmor policy to be loaded; unprivileged local users can reach parsing before permission checks through self-attribute writes or the world-writable securityfs access interface.

The record

CVE
CVE-2026-89761
Published
Sep 11, 2026
Updated
Sep 11, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

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=4.13
  2. Affected versionversion=f1bd904175e8190ce14aedee37e207ab51fe3b30 <28069434aef66b9d084f0609b7a29c171846815e
  3. Affected versionversion=f1bd904175e8190ce14aedee37e207ab51fe3b30 <36bdd0b45ec3f4822832a56e9db8674c8450dfce
  4. Affected versionversion=f1bd904175e8190ce14aedee37e207ab51fe3b30 <9124e078ea2250d8d01d2162a550acb01ef5bf48
  5. Affected versionversion=f1bd904175e8190ce14aedee37e207ab51fe3b30 <9f1e40193eef7f047e6b77cfb4b4cafdecd7a123

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.13; version=f1bd904175e8190ce14aedee37e207ab51fe3b30 <28069434aef66b9d084f0609b7a29c171846815e; version=f1bd904175e8190ce14aedee37e207ab51fe3b30 <36bdd0b45ec3f4822832a56e9db8674c8450dfce; version=f1bd904175e8190ce14aedee37e207ab51fe3b30 <9124e078ea2250d8d01d2162a550acb01ef5bf48; version=f1bd904175e8190ce14aedee37e207ab51fe3b30 <9f1e40193eef7f047e6b77cfb4b4cafdecd7a123

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.

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 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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