ksmbd: skip lock-range check on equal size to avoid size==0 underflow
Priority LOW 22Published · Updated
Key facts
- Attack vector
- —
- 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
In the Linux kernel, the following vulnerability has been resolved: ksmbd: skip lock-range check on equal size to avoid size==0 underflow When size equals the current i_size (including 0), the code used to call check_lock_range(filp, i_size, size - 1, WRITE), which computes `size - 1` and can underflow for size==0. Skip the equal case.
Why it matters now
EPSS 0.00202 10th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.1.160, 6.6.120, 6.12.64 +2
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.1.160, 6.6.120, 6.12.64, 6.18.3, 6.19
Vendor assessments
Red Hat
Not affected: 5 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2025-68786
- 2026-10-03 Alias added: GHSA-7vqw-4gww-392j
References
Other 5
- https://git.kernel.org/stable/c/52fcbb92e0d3acfd1448b2a43b6595d540da5295
- https://git.kernel.org/stable/c/da29cd197246c85c0473259f1cad897d9d28faea
- https://git.kernel.org/stable/c/a6f4cfa3783804336491e0edcb250c25f9b59d33
- https://git.kernel.org/stable/c/571204e4758a528fbd67330bd4b0dfbdafb33dd8
- https://git.kernel.org/stable/c/5d510ac31626ed157d2182149559430350cf2104
More Linux vulnerabilities
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- 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
Sources
- CVE-2025-68786 · CVE Program
- CVE-2025-68786 · NVD
- FIRST EPSS
- GHSA-7vqw-4gww-392j · GitHub Advisory Database · CC BY 4.0
- CVE-2025-68786 · Red Hat security data · CC BY 4.0
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