CVE-2026-31434

Kernel memory exhaustion via unreleased kobject names

Published Apr 22, 2026 · Updated Apr 22, 2026

Memory leak in Btrfs in Linux Kernel 6.16 and affected stable branches allows local users to exhaust kernel memory via filesystem mounts. The check_removing_space_info() path frees sub-group space_info elements without calling btrfs_sysfs_remove_space_info(), so kobject_put() never releases their kobj->name allocations. Triggering requires low-privileged local access and a Btrfs mount workflow; repeated leaks can exhaust kernel memory and interrupt the system.

CVSS severity5.5
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory leak in Btrfs in Linux Kernel 6.16 and affected stable branches allows local users to exhaust kernel memory via filesystem mounts. The check_removing_space_info() path frees sub-group space_info elements without calling btrfs_sysfs_remove_space_info(), so kobject_put() never releases their kobj->name allocations. Triggering requires low-privileged local access and a Btrfs mount workflow; repeated leaks can exhaust kernel memory and interrupt the system.

The record

CVE
CVE-2026-31434
Published
Apr 22, 2026
Updated
Apr 22, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-401, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 22, 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=0bd151ce4200ca847990e05cca29a76456982ca5 <94054ffd311a1f76b7093ba8ebf50bdb0d28337c
  2. Affected versionversion=190d5a7c4fe42b8c9aa46e3336389e7cb10395bb <1737ddeafbb1304f41ec2eede4f7366082e7c96a
  3. Affected versionversion=6.16
  4. Affected versionversion=64c7ddda83acfbaa0efb381a1928ce908c584607 <416484f21a9d1280cf6daa7ebc10c79b59c46e48
  5. Affected versionversion=f92ee31e031c7819126d2febdda0c3e91f5d2eb9 <3c645c6f7e5470debbb81666b230056de48f36dc
  6. Affected versionversion=f92ee31e031c7819126d2febdda0c3e91f5d2eb9 <3c844d01f9874a43004c82970d8da94f9aba8949
  7. Affected versionversion=f92ee31e031c7819126d2febdda0c3e91f5d2eb9 <a4376d9a5d4c9610e69def3fc0b32c86a7ab7a41

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=0bd151ce4200ca847990e05cca29a76456982ca5 <94054ffd311a1f76b7093ba8ebf50bdb0d28337c; version=190d5a7c4fe42b8c9aa46e3336389e7cb10395bb <1737ddeafbb1304f41ec2eede4f7366082e7c96a; version=6.16; version=64c7ddda83acfbaa0efb381a1928ce908c584607 <416484f21a9d1280cf6daa7ebc10c79b59c46e48; version=f92ee31e031c7819126d2febdda0c3e91f5d2eb9 <3c645c6f7e5470debbb81666b230056de48f36dc; version=f92ee31e031c7819126d2febdda0c3e91f5d2eb9 <3c844d01f9874a43004c82970d8da94f9aba8949; version=f92ee31e031c7819126d2febdda0c3e91f5d2eb9 <a4376d9a5d4c9610e69def3fc0b32c86a7ab7a41

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5UbuntuCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.004Application or System Exploitation

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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