CVE-2026-46186
published 2026-05-28CVE-2026-46186: In the Linux kernel, the following vulnerability has been resolved: Bluetooth: virtio_bt: validate rx pkt_type header length virtbt_rx_handle() reads the…
high7
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: virtio_bt: validate rx pkt_type header length
virtbt_rx_handle() reads the leading pkt_type byte from the RX skb
and forwards the remainder to hci_recv_frame() for every
event/ACL/SCO/ISO type, without checking that the remaining payload
is at least the fixed HCI header for that type.
After the preceding patch bounds the backend-supplied used.len to
[1, VIRTBT_RX_BUF_SIZE], a one-byte completion still reaches
hci_recv_frame() with skb->len already pulled to 0. If the byte
happened to be HCI_ACLDATA_PKT, the ACL-vs-ISO classification
fast-path in hci_dev_classify_pkt_type() dereferences
hci_acl_hdr(skb)->handle whenever the HCI device has an active
CIS_LINK, BIS_LINK, or PA_LINK connection, reading two bytes of
uninitialized RX-buffer data. The same hazard exists for every
packet type the driver accepts because none of the switch cases in
virtbt_rx_handle() check skb->len against the per-type minimum HCI
header size before handing the frame to the core.
After stripping pkt_type, require skb->len to cover the fixed
header size for the selected type (event 2, ACL 4, SCO 3, ISO 4)
before calling hci_recv_frame(); drop ratelimited otherwise.
Unknown pkt_type values still take the original kfree_skb() default
path.
Use bt_dev_err_ratelimited() because both the length and pkt_type
values come from an untrusted backend that can otherwise flood the
kernel log.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 7b2d4c04816cdc887f472caaf7fc966cfc107e40 | 7b2d4c04816cdc887f472caaf7fc966cfc107e40 |
| linux | linux | >= 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 1e1e509b6fd2a42421745bbcd98bd16daad20904 | 1e1e509b6fd2a42421745bbcd98bd16daad20904 |
| linux | linux | >= 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 2c1143564c71e7497b42d8360a8379ccbb011d3c | 2c1143564c71e7497b42d8360a8379ccbb011d3c |
| linux | linux | >= 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < 3485c7236c59c8c34a41af1c4b52982437554e79 | 3485c7236c59c8c34a41af1c4b52982437554e79 |
| linux | linux | >= 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < f743eab6486965f276c7e3f1700895f014fdc6db | f743eab6486965f276c7e3f1700895f014fdc6db |
| linux | linux | >= 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be < daf23014e5d975e72ea9c02b5160d3fcf070ea47 | daf23014e5d975e72ea9c02b5160d3fcf070ea47 |
| linux | linux | >= 5.15.78 < 5.15.209 | 5.15.209 |
| linux | linux | >= 6.0.8 < 6.1 | 6.1 |
| linux | linux | >= cf2719a21fdb9d4c8e9c834d279163609bef575d < 149cfb42ad69c7964fd9f2c43831da9152007129 | 149cfb42ad69c7964fd9f2c43831da9152007129 |
| linux | linux_kernel | — | — |