CVE-2026-99163

Invalid kernel reads via stacktrace type confusion

Published Oct 28, 2026 · Updated Oct 28, 2026

Type confusion in Linux tracing histograms allows local users to trigger invalid kernel reads through crafted synthetic events. The check_synth_field() function accepts signed eight-byte scalars as stacktrace fields, causing get_field_size() and trace_stack() to dereference scalar values as pointers. Exploitation requires write access to tracing controls; the published evidence does not establish code execution or the resulting failure mode.

CVSS severityUnavailable
Unscored
EPSS probability0.13%
Next 30 days · Nov 1, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Type confusion in Linux tracing histograms allows local users to trigger invalid kernel reads through crafted synthetic events. The check_synth_field() function accepts signed eight-byte scalars as stacktrace fields, causing get_field_size() and trace_stack() to dereference scalar values as pointers. Exploitation requires write access to tracing controls; the published evidence does not establish code execution or the resulting failure mode.

The record

CVE
CVE-2026-99163
Published
Oct 28, 2026
Updated
Oct 28, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 28, 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=00cf3d672a9dd409418647e9f98784c339c3ff63 <1f36e4ddd05d540f363dbaa4c23042549f15b3ef
  2. Affected versionversion=00cf3d672a9dd409418647e9f98784c339c3ff63 <a244c241593b5b38a08f0df2cb43c26574efbdcb
  3. Affected versionversion=00cf3d672a9dd409418647e9f98784c339c3ff63 <deb336ae7c7b341591a6862cf6fcfeca97c77dfd
  4. Affected versionversion=5.10.237 <5.11
  5. Affected versionversion=5.15.124 <5.16
  6. Affected versionversion=5f52389bdd9eafb63b3a2f804e02aeb17b6a5f55
  7. Affected versionversion=6.1.43 <6.2
  8. Affected versionversion=6.3
  9. Affected versionversion=b9453380c1c542fd095a4dbe9251eeba4022bbce
  10. Affected versionversion=f3baa42afeea0d5f04ad31525e861199d02210cc

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=00cf3d672a9dd409418647e9f98784c339c3ff63 <1f36e4ddd05d540f363dbaa4c23042549f15b3ef; version=00cf3d672a9dd409418647e9f98784c339c3ff63 <a244c241593b5b38a08f0df2cb43c26574efbdcb; version=00cf3d672a9dd409418647e9f98784c339c3ff63 <deb336ae7c7b341591a6862cf6fcfeca97c77dfd; version=5.10.237 <5.11; version=5.15.124 <5.16; version=5f52389bdd9eafb63b3a2f804e02aeb17b6a5f55; version=6.1.43 <6.2; version=6.3; version=b9453380c1c542fd095a4dbe9251eeba4022bbce; version=f3baa42afeea0d5f04ad31525e861199d02210cc

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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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