published September 17, 2026
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: virtio_bt: avoid OOB read of build info string
The virtbt_setup_zephyr() sends the Zephyr vendor command 0xfc08 (Read
Build Information) and hands the response to bt_dev_info() and
hci_set_fw_info() as a "%s" string starting at skb->data + 1, without
checking the length. A backend that answers with status only leaves that
pointer past the end of the received data, so the walk reads adjacent
slab memory until it meets a NUL. Those bytes reach the kernel log and
the firmware-info debugfs file.
To fix this, print the string with a bounded "%.*s" limited to
skb->len - 1. A short or unterminated response then prints as much as
arrived instead of failing setup.
This mirrors commit dd068ef04412 ("Bluetooth: bpa10x: avoid OOB read of
revision string in bpa10x_setup()"), which fixed the identical pattern.