CVE-2026-72310

smb: client: fix overflow in passthrough ioctl bounds check

HIGH
8.1
CVSS Score
Published: August 15, 2026 at 05:55 AM UTC
Updated: October 16, 2026 at 07:17 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH8.1
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix overflow in passthrough ioctl bounds check smb2_ioctl_query_info() validates the PASSTHRU_FSCTL response payload before copying it to userspace. The payload offset and length both come from 32-bit fields. The bounds check currently adds OutputOffset and qi.input_buffer_length directly, so the addition can wrap in 32-bit arithmetic before the result is compared against the response buffer length. A malicious server can use a large OutputOffset and a small OutputCount to make the wrapped sum pass the bounds check. The later copy_to_user() then reads from io_rsp + OutputOffset, outside the response buffer. Use size_add() for the offset plus length check so overflow is treated as out of bounds.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2005c32ec99ee2490e8131b3953f3f212009ffea2b1116bbe898aefdf584838448c6869f69851e0f5.4.695.5
Vendor states this is fixed in 160045fc943f6c46b227644261252c8a22b8a87a (fixed)
Vendor states this is fixed in 1627e7d5c9b09721a141d07cedb178882f1ded67 (fixed)
Vendor states this is fixed in 175357ee0c596cb82054650dfa32fda51ad35aaa (fixed)
Vendor states this is fixed in 1a638c55f2db6cb2296e5e3138015dd8fd9d4aa9 (fixed)
Vendor states this is fixed in 63feb687e89a3a52a31e6e01764117cc500f1974 (fixed)
Vendor states this is fixed in a4f27ad055392fa164f5649e89a3637b033c5fcc (fixed)
Vendor states this is fixed in b30771b69eafae750afb7385fbcc3d77ed3f3670 (fixed)
Vendor states this is fixed in dbd126539c098dba3159ce7d34b10b2daddcbd0f (fixed)
Vendor states this is fixed in 5.10.261 (unaffected)
Vendor states this is fixed in 5.15.212 (unaffected)
Vendor states this is fixed in 5.5 (unaffected)
Vendor states this is fixed in 6.1.178 (unaffected)
Vendor states this is fixed in 6.12.97 (unaffected)
Vendor states this is fixed in 6.18.40 (unaffected)
Vendor states this is fixed in 6.6.145 (unaffected)
Vendor states this is fixed in 7.1.5 (unaffected)
Vendor states this is fixed in 7.2 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.1HIGHLinux
Vector?

Quick Info

StatusRECEIVED

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