CVE-2026-89897Hinoki check available

Kernel crash via exclusive follower pointer race

Published Sep 16, 2026 · Updated Sep 16, 2026

A race condition in the Linux kernel HDMI CEC framework allows local users to trigger a use-after-free during exclusive follower delivery. The cec_receive_notify() function reads and queues through adap->cec_follower without holding the adapter mutex while another thread can change follower mode or release the filehandle. Triggering requires access to a CEC device and concurrent message reception, and the resulting stale-pointer access can corrupt kernel memory or crash the system.

CVSS severityUnavailable
Unscored
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

A race condition in the Linux kernel HDMI CEC framework allows local users to trigger a use-after-free during exclusive follower delivery. The cec_receive_notify() function reads and queues through adap->cec_follower without holding the adapter mutex while another thread can change follower mode or release the filehandle. Triggering requires access to a CEC device and concurrent message reception, and the resulting stale-pointer access can corrupt kernel memory or crash the system.

The record

CVE
CVE-2026-89897
Published
Sep 16, 2026
Updated
Sep 16, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=4.8
  2. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <1924d0788caa6c66fd320dd4704fae99487fd2c7
  3. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <271e57a936dcdbaecb4b1bd005d9a285bbe60ab4
  4. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <4b532b271c91790b7ab661cd488a7ad36f5c4f6b
  5. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <5c62095acc2a952099688774513c4a637bcdb2b5
  6. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <ae614f48712156fb0f55b207338d48d422c58bc0
  7. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <cac577854826950dda4d53569728b1da6c1425d5
  8. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <df941e6851da17fc53c7f6af2bdcc7383d17babc
  9. Affected versionversion=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <efc829b4b937f98c4467bffe9243f756b7cfbf7f

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=4.8; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <1924d0788caa6c66fd320dd4704fae99487fd2c7; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <271e57a936dcdbaecb4b1bd005d9a285bbe60ab4; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <4b532b271c91790b7ab661cd488a7ad36f5c4f6b; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <5c62095acc2a952099688774513c4a637bcdb2b5; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <ae614f48712156fb0f55b207338d48d422c58bc0; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <cac577854826950dda4d53569728b1da6c1425d5; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <df941e6851da17fc53c7f6af2bdcc7383d17babc; version=9881fe0ca187c213eb3a6a8e78e45ad4d1cec171 <efc829b4b937f98c4467bffe9243f756b7cfbf7f

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 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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