CVE-2025-39776

Local system crash via stale page-table reuse

Published Sep 11, 2025 · Updated Sep 11, 2025

Use-after-free in affected Linux kernel branches allows local users to crash debug kernels through stale page-table reuse. destroy_args() in mm/debug_vm_pgtable.c frees manually allocated page-table structures without first calling the matching *_clear operations, leaving live entries that a later mm_struct can inherit. Reachability requires CONFIG_DEBUG_VM_PGTABLE=y and rare allocator reuse; successful triggering can corrupt kernel memory or panic the host.

CVSS severity7.8
High
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in affected Linux kernel branches allows local users to crash debug kernels through stale page-table reuse. destroy_args() in mm/debug_vm_pgtable.c frees manually allocated page-table structures without first calling the matching *_clear operations, leaving live entries that a later mm_struct can inherit. Reachability requires CONFIG_DEBUG_VM_PGTABLE=y and rare allocator reuse; successful triggering can corrupt kernel memory or panic the host.

The record

CVE
CVE-2025-39776
Published
Sep 11, 2025
Updated
Sep 11, 2025
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 11, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 11, 2025Record 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=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <47d2a149611b8a94d24add9868c442a4af278658
  2. Affected versionversion=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <561171db3b3eb759ba3f284dba7a76f4476ade03
  3. Affected versionversion=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <61a9f2e5c49f05e3ea2c16674540a075a1b4be6f
  4. Affected versionversion=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <63962ff932ef359925b94be2a88df6b4fd4fed0a
  5. Affected versionversion=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <7bf57a0709cd7c9088cea8de023d6f4fbf2518b0
  6. Affected versionversion=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <dde30854bddfb5d69f30022b53c5955a41088b33
  7. Affected versionversion=5.15

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <47d2a149611b8a94d24add9868c442a4af278658; version=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <561171db3b3eb759ba3f284dba7a76f4476ade03; version=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <61a9f2e5c49f05e3ea2c16674540a075a1b4be6f; version=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <63962ff932ef359925b94be2a88df6b4fd4fed0a; version=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <7bf57a0709cd7c9088cea8de023d6f4fbf2518b0; version=3c9b84f044a9e54cf56d1b2c9b80a2d2ce56d70a <dde30854bddfb5d69f30022b53c5955a41088b33; version=5.15

Published CVSS scores

7.8UbuntuCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
5.7UbuntuCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.8NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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