CVE-2026-31410Network attack vector

NT hash disclosure via volume identifier response

Published Apr 6, 2026 · Updated Apr 6, 2026

Information disclosure in Linux Kernel ksmbd 5.15 through 7.0-rc4 allows remote authenticated users to obtain the account's NT hash. The FS_OBJECT_ID_INFORMATION handler in fs/smb/server/smb2pdu.c copies user_passkey(sess->user) into a 16-byte volume object identifier returned to the SMB client. Reachability requires an authenticated non-guest ksmbd session and a filesystem-information query; the disclosed NT hash supports offline password cracking.

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

What happened

Information disclosure in Linux Kernel ksmbd 5.15 through 7.0-rc4 allows remote authenticated users to obtain the account's NT hash. The FS_OBJECT_ID_INFORMATION handler in fs/smb/server/smb2pdu.c copies user_passkey(sess->user) into a 16-byte volume object identifier returned to the SMB client. Reachability requires an authenticated non-guest ksmbd session and a filesystem-information query; the disclosed NT hash supports offline password cracking.

The record

CVE
CVE-2026-31410
Published
Apr 6, 2026
Updated
Apr 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 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 <3a64125730cabc34fccfbc230c2667c2e14f7308
  2. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3d80ebe6d1b7bc9ad20fd9b0c1a0c56d804f8a0a
  3. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c283a6ffe6d5d6e5594d991286b9ce15951572e1
  4. Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ce00616bc1df675bfdacc968f2bf7c51f4669227

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3a64125730cabc34fccfbc230c2667c2e14f7308; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3d80ebe6d1b7bc9ad20fd9b0c1a0c56d804f8a0a; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c283a6ffe6d5d6e5594d991286b9ce15951572e1; version=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ce00616bc1df675bfdacc968f2bf7c51f4669227

Published CVSS scores

5.5NVDCVSS: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

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1003OS Credential Dumping

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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