CVE-2026-99187

Stranded perf events via premature migration traversal

Published Oct 28, 2026 · Updated Oct 28, 2026

Incorrect perf migration in Linux 6.2 allows attackers to leave PMU events on an offlining CPU via CPU hot-unplug. In kernel/events/core.c, __perf_pmu_remove() removes a group leader from the tree being traversed, causing rb_next() to terminate iteration before all groups migrate. The condition requires active PMU events and CPU hot-unplug; attacker control and consequences beyond violated driver assumptions are undisclosed.

CVSS severityUnavailable
Unscored
EPSS probability0.17%
Next 30 days · Nov 1, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect perf migration in Linux 6.2 allows attackers to leave PMU events on an offlining CPU via CPU hot-unplug. In kernel/events/core.c, __perf_pmu_remove() removes a group leader from the tree being traversed, causing rb_next() to terminate iteration before all groups migrate. The condition requires active PMU events and CPU hot-unplug; attacker control and consequences beyond violated driver assumptions are undisclosed.

The record

CVE
CVE-2026-99187
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=6.2
  2. Affected versionversion=bd27568117664b8b3e259721393df420ed51f57b <3eb08f09bfb364051f51316da873c3bd51a839ef
  3. Affected versionversion=bd27568117664b8b3e259721393df420ed51f57b <e76b36b4be7160eaa14b416681e548b125702395
  4. Affected versionversion=bd27568117664b8b3e259721393df420ed51f57b <f5f0028764de322a3d04eda0d3b6389ca9847446

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=6.2; version=bd27568117664b8b3e259721393df420ed51f57b <3eb08f09bfb364051f51316da873c3bd51a839ef; version=bd27568117664b8b3e259721393df420ed51f57b <e76b36b4be7160eaa14b416681e548b125702395; version=bd27568117664b8b3e259721393df420ed51f57b <f5f0028764de322a3d04eda0d3b6389ca9847446

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.

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Technologies

Your stack

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