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NVD / CVE Program· CNA Linux

CVE-2026-31434: btrfs: fix leak of kobject name for sub-group space_info

Noroxi assessment

Priority: Monitor (action score 22/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.12% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 1737ddeafbb1304f41ec2eede4f7366082e7c96a, 3c645c6f7e5470debbb81666b230056de48f36dc, 3c844d01f9874a43004c82970d8da94f9aba8949.

Low priority for now. Upgrade to Linux Linux 1737ddeafbb1304f41ec2eede4f7366082e7c96a, 3c645c6f7e5470debbb81666b230056de48f36dc, 3c844d01f9874a43004c82970d8da94f9aba8949 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix leak of kobject name for sub-group space_info When create_space_info_sub_group() allocates elements of space_info->sub_group[], kobject_init_and_add() is called for each element via btrfs_sysfs_add_space_info_type(). However, when check_removing_space_info() frees these elements, it does not call btrfs_sysfs_remove_space_info() on them. As a result, kobject_put() is not called and the associated kobj->name objects are leaked. This memory leak is reproduced by running the blktests test case zbd/009 on kernels built with CONFIG_DEBUG_KMEMLEAK. The kmemleak feature reports the following error: unreferenced object 0xffff888112877d40 (size 16): comm "mount", pid 1244, jiffies 4294996972 hex dump (first 16 bytes): 64 61 74 61 2d 72 65 6c 6f 63 00 c4 c6 a7 cb 7f data-reloc...... backtrace (crc 53ffde4d): __kmalloc_node_track_caller_noprof+0x619/0x870 kstrdup+0x42/0xc0 kobject_set_name_vargs+0x44/0x110 kobject_init_and_add+0xcf/0x150 btrfs_sysfs_add_space_info_type+0xfc/0x210 [btrfs] create_space_info_sub_group.constprop.0+0xfb/0x1b0 [btrfs] create_space_info+0x211/0x320 [btrfs] btrfs_init_space_info+0x15a/0x1b0 [btrfs] open_ctree+0x33c7/0x4a50 [btrfs] btrfs_get_tree.cold+0x9f/0x1ee [btrfs] vfs_get_tree+0x87/0x2f0 vfs_cmd_create+0xbd/0x280 __do_sys_fsconfig+0x3df/0x990 do_syscall_64+0x136/0x1540 entry_SYSCALL_64_after_hwframe+0x76/0x7e To avoid the leak, call btrfs_sysfs_remove_space_info() instead of kfree() for the elements.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Apr 22, 2026
Updated
Jun 17, 2026
EPSS
0.1% · 2th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

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  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

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  • when exploit code appears or is weaponized
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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel6.1.162 and later · before 6.1.168
  • linux linux kernel6.6.122 and later · before 6.6.131
  • linux linux kernel6.12.67 and later · before 6.12.80
  • linux linux kernel6.16 and later · before 6.18.21
  • linux linux kernel6.19 and later · before 6.19.11
  • linux linux kernel7.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 6.16affected
    • 64c7ddda83acfbaa0efb381a1928ce908c584607 and later · before 416484f21a9d1280cf6daa7ebc10c79b59c46e48affected · git
    • 0bd151ce4200ca847990e05cca29a76456982ca5 and later · before 94054ffd311a1f76b7093ba8ebf50bdb0d28337caffected · git
    • 190d5a7c4fe42b8c9aa46e3336389e7cb10395bb and later · before 1737ddeafbb1304f41ec2eede4f7366082e7c96aaffected · git
    • f92ee31e031c7819126d2febdda0c3e91f5d2eb9 and later · before 3c844d01f9874a43004c82970d8da94f9aba8949affected · git
    • f92ee31e031c7819126d2febdda0c3e91f5d2eb9 and later · before 3c645c6f7e5470debbb81666b230056de48f36dcaffected · git
    • f92ee31e031c7819126d2febdda0c3e91f5d2eb9 and later · before a4376d9a5d4c9610e69def3fc0b32c86a7ab7a41affected · git
    • 6.1.162 and later · before 6.1.168affected · semver
    • 6.6.122 and later · before 6.6.131affected · semver
    • 6.12.67 and later · before 6.12.80affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.170-16.1.170-1
Debian:13linuxbefore 6.12.85-16.12.85-1
Debian:14linuxbefore 6.19.11-16.19.11-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-31433Apr 22, 2026 · ksmbd: fix potencial OOB in get_file_all_info() for compound requests
    35Monitor
  • ← EarlierCVE-2026-31432Apr 22, 2026 · ksmbd: fix OOB write in QUERY_INFO for compound requests
    35Monitor
  • Later →CVE-2026-31437Apr 22, 2026 · netfs: Fix NULL pointer dereference in netfs_unbuffered_write() on retry
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux1737ddeafbb1304f41ec2eede4f7366082e7c96aVendor (CNA)
Linux Linux3c645c6f7e5470debbb81666b230056de48f36dcVendor (CNA)
Linux Linux3c844d01f9874a43004c82970d8da94f9aba8949Vendor (CNA)
Linux Linux416484f21a9d1280cf6daa7ebc10c79b59c46e48Vendor (CNA)
Linux Linux6.1.168Vendor (CNA)
Linux Linux6.12.80Vendor (CNA)
Linux Linux6.6.131Vendor (CNA)
Linux Linux94054ffd311a1f76b7093ba8ebf50bdb0d28337cVendor (CNA)
Linux Linuxa4376d9a5d4c9610e69def3fc0b32c86a7ab7a41Vendor (CNA)
debian:linux6.1.170-1 · Debian:12Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-401 · Missing Release of Memory after Effective Lifetime

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (5 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records