CVE-2026-98420Network attack vector

Mapped-drive disruption via premature session destruction

Published Oct 14, 2026 · Updated Oct 14, 2026

Session expiration errors in Linux 6.4 ksmbd allow remote authenticated users to interrupt mapped-drive access via SMB session setup. ksmbd_session_register() treats ten seconds of inactivity as credential expiration and destroys valid sessions when another SessionSetup exchange begins. With ksmbd enabled, additional sessions on the same connection invalidate existing tree connects, causing mapped-drive failures rather than a reported kernel crash.

CVSS severityUnavailable
Unscored
EPSS probability0.24%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Session expiration errors in Linux 6.4 ksmbd allow remote authenticated users to interrupt mapped-drive access via SMB session setup. ksmbd_session_register() treats ten seconds of inactivity as credential expiration and destroys valid sessions when another SessionSetup exchange begins. With ksmbd enabled, additional sessions on the same connection invalidate existing tree connects, causing mapped-drive failures rather than a reported kernel crash.

The record

CVE
CVE-2026-98420
Published
Oct 14, 2026
Updated
Oct 14, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 14, 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=1fc8a2b14ef5223f8e0b95faba2ee0a6e4d0f99d
  2. Affected versionversion=5.15.145 <5.16
  3. Affected versionversion=6.1.29 <6.2
  4. Affected versionversion=6.2.16 <6.3
  5. Affected versionversion=6.3.2 <6.4
  6. Affected versionversion=6.4
  7. Affected versionversion=6775ee7ef4b37c521aa4cf3730f54554c4875542
  8. Affected versionversion=750a2d772e9d9ff377fd32e3b6797bf2cd847a7a
  9. Affected versionversion=a6a9601ba995d0fec635324cb9fd8d14f9bea14e
  10. Affected versionversion=ea174a91893956450510945a0c5d1a10b5323656 <c99ea7855124ca1428a1e59c2b4590aaef34eacf
  11. Affected versionversion=ea174a91893956450510945a0c5d1a10b5323656 <d7fd1f98607f2cd358e583f9548bdf0173090a86

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=1fc8a2b14ef5223f8e0b95faba2ee0a6e4d0f99d; version=5.15.145 <5.16; version=6.1.29 <6.2; version=6.2.16 <6.3; version=6.3.2 <6.4; version=6.4; version=6775ee7ef4b37c521aa4cf3730f54554c4875542; version=750a2d772e9d9ff377fd32e3b6797bf2cd847a7a; version=a6a9601ba995d0fec635324cb9fd8d14f9bea14e; version=ea174a91893956450510945a0c5d1a10b5323656 <c99ea7855124ca1428a1e59c2b4590aaef34eacf; version=ea174a91893956450510945a0c5d1a10b5323656 <d7fd1f98607f2cd358e583f9548bdf0173090a86

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
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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