CVE-2026-43245Network attack vector

System hang via blocking NTFS dentry comparison

Published May 6, 2026 · Updated May 6, 2026

Use of a blocking allocator in Linux Kernel NTFS3 allows remote attackers to hang the kernel through crafted pathname lookups. The ntfs_d_compare callback calls __getname(), which can sleep while VFS performs an RCU-walk comparison that must not block, instead of using a nonblocking allocation. Remote reachability requires a network file service backed by an NTFS3 volume and a lookup that enters the case-insensitive slow path; the bounded consequence is a system hang.

CVSS severity7.5
High
EPSS probability0.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use of a blocking allocator in Linux Kernel NTFS3 allows remote attackers to hang the kernel through crafted pathname lookups. The ntfs_d_compare callback calls __getname(), which can sleep while VFS performs an RCU-walk comparison that must not block, instead of using a nonblocking allocation. Remote reachability requires a network file service backed by an NTFS3 volume and a lookup that enters the case-insensitive slow path; the bounded consequence is a system hang.

The record

CVE
CVE-2026-43245
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 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=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <142c444a395f4d26055c8a4473e228bb86283f1e
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ca2a04e84af79596e5cd9cfe697d5122ec39c8ce
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fb4b1f969ba01fa1d4088467a02fc1e5f0806710

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <142c444a395f4d26055c8a4473e228bb86283f1e; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ca2a04e84af79596e5cd9cfe697d5122ec39c8ce; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <fb4b1f969ba01fa1d4088467a02fc1e5f0806710

Published CVSS scores

7.5kernel.orgCVSS:3.1/AV:N/AC:L/PR:N/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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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