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TI-2026-79658 Aliases CVE-2026-98901GHSA-6w2x-j37m-r6r9

Lease break and acknowledgment handling flaw in Linux kernel ksmbd

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Fixed

No CVSS vector from any source. Fix status from CNA.

Summary

The Linux kernel ksmbd SMB server, from version 5.15, mishandles SMB2 lease state handling. When breaking level-II or read leases for writes and truncates, ksmbd skips valid lease states that contain WRITE_CACHING, and it does not apply lease break acknowledgments according to the SMB2 rule that the acknowledged state must be a subset of the server's break target.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix lease break and ack state handling Do not skip valid lease states containing WRITE_CACHING when breaking level-II/read leases for writes and truncates. Handle lease break acknowledgments according to the SMB2 rule that the acknowledged state must be a subset of the server's break target. Apply the acknowledged state directly and keep the break pending on failed ACKs.

Why it matters now

EPSS 0.00174 6th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.6.158, 6.12.111, 6.18.53 +1

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15 and later6.6.158, 6.12.111, 6.18.53, 7.2Patch availableCNA
  • Linux VendorLinux Affected 5.15 and later Fixed in 6.6.158, 6.12.111, 6.18.53, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Update the Linux kernel to a fixed version: 6.6.158, 6.12.111, 6.18.53 or 7.2.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 6.6.158, 6.12.111, 6.18.53, 7.2

Timeline

  1. 2026-10-23 Threatist record created from CVE-2026-98901
  2. 2026-10-23 Alias added: GHSA-6w2x-j37m-r6r9
  3. 2026-10-26 Fix available: Linux/Linux@0 · CNA

References

Other 4

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21727 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences