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NVD / CVE Program· CNA Linux

CVE-2025-71237: nilfs2: Fix potential block overflow that cause system hang

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: 0.13% (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 2438982f635e6cc2009be68ba2efb2998727d8d4, 4aa45f841413cca81882602b4042c53502f34cad, 6457d3ee41a4c15082ac49c5aa7fb933b4a043f3; cbl2 kernel 5.15.200.1-1 on CBL Mariner 2.0 5.15.202.1-1.

Low priority for now. Upgrade to Linux Linux 2438982f635e6cc2009be68ba2efb2998727d8d4, 4aa45f841413cca81882602b4042c53502f34cad, 6457d3ee41a4c15082ac49c5aa7fb933b4a043f3; cbl2 kernel 5.15.200.1-1 on CBL Mariner 2.0 5.15.202.1-1 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: nilfs2: Fix potential block overflow that cause system hang When a user executes the FITRIM command, an underflow can occur when calculating nblocks if end_block is too small. Since nblocks is of type sector_t, which is u64, a negative nblocks value will become a very large positive integer. This ultimately leads to the block layer function __blkdev_issue_discard() taking an excessively long time to process the bio chain, and the ns_segctor_sem lock remains held for a long period. This prevents other tasks from acquiring the ns_segctor_sem lock, resulting in the hang reported by syzbot in [1]. If the ending block is too small, typically if it is smaller than 4KiB range, depending on the usage of the segment 0, it may be possible to attempt a discard request beyond the device size causing the hang. Exiting successfully and assign the discarded size (0 in this case) to range->len. Although the start and len values in the user input range are too small, a conservative strategy is adopted here to safely ignore them, which is equivalent to a no-op; it will not perform any trimming and will not throw an error. [1] task:segctord state:D stack:28968 pid:6093 tgid:6093 ppid:2 task_flags:0x200040 flags:0x00080000 Call Trace: rwbase_write_lock+0x3dd/0x750 kernel/locking/rwbase_rt.c:272 nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2569 [inline] nilfs_segctor_thread+0x6ec/0xe00 fs/nilfs2/segment.c:2684 [ryusuke: corrected part of the commit message about the consequences]

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Feb 18, 2026
Updated
Jun 17, 2026
EPSS
0.1% · 3th percentile
CWE
—

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%

Get told when this record changes

  • 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 you'll hear from us

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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 kernel3.15 and later · before 5.10.251
  • linux linux kernel5.11 and later · before 5.15.201
  • linux linux kernel5.16 and later · before 6.1.164
  • linux linux kernel6.2 and later · before 6.6.125
  • linux linux kernel6.7 and later · before 6.12.72
  • linux linux kernel6.13 and later · before 6.18.11
  • linux linux kernel6.19 and later · before 6.19.1

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

    • 3.15affected
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before 6457d3ee41a4c15082ac49c5aa7fb933b4a043f3affected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before ba18e5f22f26aa4ef78bc3e81f639d1d4f3845e6affected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before 2438982f635e6cc2009be68ba2efb2998727d8d4affected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before df1e20796c9f3d541cca47fb72e4369ea135642daffected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before ea2278657ad0d62596589fbe2caf995e189e65e7affected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before 4aa45f841413cca81882602b4042c53502f34cadaffected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before b8c5ee234bd54f1447c846101fdaef2cf70c2149affected · git
    • 82e11e857be3ffd2a0a952c9db8aa2379e2b9e44 and later · before ed527ef0c264e4bed6c7b2a158ddf516b17f5f66affected · git
    • before 3.15not affected · semver

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:11linuxbefore 5.10.251-15.10.251-1
Debian:12linuxbefore 6.1.164-16.1.164-1
Debian:13linuxbefore 6.12.73-16.12.73-1
Debian:14linuxbefore 6.18.12-16.18.12-1
openSUSE:Tumbleweedkernel-sourcebefore 6.19.8-1.16.19.8-1.1

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-2025-71230Feb 18, 2026 · hfs: ensure sb->s_fs_info is always cleaned up
    22Monitor
  • ← EarlierCVE-2025-71233Feb 18, 2026 · PCI: endpoint: Avoid creating sub-groups asynchronously
    22Monitor
  • Later →CVE-2026-23220Feb 18, 2026 · ksmbd: fix infinite loop caused by next_smb2_rcv_hdr_off reset in error paths
    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 Linux2438982f635e6cc2009be68ba2efb2998727d8d4Vendor (CNA)
Linux Linux4aa45f841413cca81882602b4042c53502f34cadVendor (CNA)
Linux Linux6457d3ee41a4c15082ac49c5aa7fb933b4a043f3Vendor (CNA)
Linux Linuxb8c5ee234bd54f1447c846101fdaef2cf70c2149Vendor (CNA)
Linux Linuxba18e5f22f26aa4ef78bc3e81f639d1d4f3845e6Vendor (CNA)
Linux Linuxdf1e20796c9f3d541cca47fb72e4369ea135642dVendor (CNA)
Linux Linuxea2278657ad0d62596589fbe2caf995e189e65e7Vendor (CNA)
Linux Linuxed527ef0c264e4bed6c7b2a158ddf516b17f5f66Vendor (CNA)
cbl2 kernel 5.15.200.1-1 on CBL Mariner 2.05.15.202.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
debian:linux6.1.164-1 · Debian:12Package registry (OSV)
opensuse:kernel-source6.19.8-1.1 · openSUSE:TumbleweedPackage 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)

—

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 (7 more)

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

All records