CVE-2026-72310

About vulnerability

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 product:

AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Debian 11 ELS , TuxCare 9.6 ESU

Affected packages:

kernel @ 5.14.0 (+6 more)

Live-patch status from KernelCare for each operating system.