DAMON monitoring hang via overflowing merge threshold
Published Sep 16, 2026 · Updated Sep 16, 2026
Integer overflow in Linux kernel DAMON allows local users with administrative access to hang a monitoring thread through extreme settings. kdamond_merge_regions() doubles an unsigned merge threshold before testing its ceiling, so values above UINT_MAX / 2 wrap and evade loop termination while regions remain over the configured limit. The condition requires root-controlled DAMON parameters, an unrealistically large aggregation-to-sampling ratio, and numerous noncontiguous regions; the impact is confined to an infinite DAMON worker loop.
Summary
What happened
Integer overflow in Linux kernel DAMON allows local users with administrative access to hang a monitoring thread through extreme settings. kdamond_merge_regions() doubles an unsigned merge threshold before testing its ceiling, so values above UINT_MAX / 2 wrap and evade loop termination while regions remain over the configured limit. The condition requires root-controlled DAMON parameters, an unrealistically large aggregation-to-sampling ratio, and numerous noncontiguous regions; the impact is confined to an infinite DAMON worker loop.
The record
- CVE
- CVE-2026-89796
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- 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?
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- Affected versionversion=11078e2d11465518a9e85096bd28f8cd5fa1ea41
- Affected versionversion=1e865019cef354a5f0314491b4b4fc9f9a613642
- Affected versionversion=310d6c15e9104c99d5d9d0ff8e5383a79da7d5e6 <123e4619ab6c8ab1c4cb1d7a58311a2af13929cd
- Affected versionversion=310d6c15e9104c99d5d9d0ff8e5383a79da7d5e6 <8a96a06e04d210845be5d9581c0e9e338947e8f8
- Affected versionversion=5.15.164 <5.16
- Affected versionversion=6.10
- Affected versionversion=6.1.101 <6.2
- Affected versionversion=6.6.41 <6.7
- Affected versionversion=6.9.10 <6.10
- Affected versionversion=d7eda72e59bbf3ed592db7ff0fd8c246c73149a8
- Affected versionversion=f2bd3184b6aeca6a497394b558337246e09fc02d
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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