In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: virtio_bt: clamp rx length before skb_put
virtbt_rx_work() calls skb_put(skb, len) where len comes directly
from virtqueue_get_buf() with no validation against the buffer we
posted to the device. The RX skb is allocated in virtbt_add_inbuf()
and exposed to virtio as exactly 1000 bytes via sg_init_one().
Checking len against skb_tailroom(skb) is not sufficient because
alloc_skb() can leave more tailroom than the 1000 bytes actually
handed to the device. A malicious or buggy backend can therefore
report used.len between 1001 and skb_tailroom(skb), causing skb_put()
to include uninitialized kernel heap bytes that were never written by
the device.
The same path also accepts len == 0, in which case skb_put(skb, 0)
leaves the skb empty but virtbt_rx_handle() still reads the pkt_type
byte from skb->data, consuming uninitialized memory.
Define VIRTBT_RX_BUF_SIZE once and reuse it in alloc_skb() and
sg_init_one(), and gate virtbt_rx_work() on that same constant so
the bound checked matches the buffer actually exposed to the device.
Reject used.len == 0 in the same gate so an empty completion can
no longer reach virtbt_rx_handle().
Use bt_dev_err_ratelimited() because the length value comes from an
untrusted backend that can otherwise flood the kernel log.
Same class of bug as commit c04db81cd028 ("net/9p: Fix buffer
overflow in USB transport layer"), which hardened the USB 9p
transport against unchecked device-reported length.
References
Configurations
Configuration 1 (hide)
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History
24 Jun 2026, 16:51
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.1:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.1:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.1:rc8:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.1:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.1:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.1:-:*:*:*:*:*:* |
|
| References | () https://git.kernel.org/stable/c/21bd244b6de5d2fe1063c23acc93fbdd2b20d112 - Patch | |
| References | () https://git.kernel.org/stable/c/4236e55b2d9d1ffd3b4bdf8ebbb86e5a0a526b4a - Patch | |
| References | () https://git.kernel.org/stable/c/6c1730099a6fc18b183bd6c1adad3b54adcaeda9 - Patch | |
| References | () https://git.kernel.org/stable/c/b40cdd1b1370d76e9e760af4490cb4a351cceead - Patch | |
| References | () https://git.kernel.org/stable/c/e6b4296f170d949ebba937cf6a3f247ec9550d2c - Patch | |
| References | () https://git.kernel.org/stable/c/ed41c81d30b211a671667259c3b5feeba0e062d5 - Patch | |
| References | () https://git.kernel.org/stable/c/fd91fa2678ab603dfb285416c1cf3843d7be1e41 - Patch | |
| First Time |
Linux linux Kernel
Linux |
|
| CWE | CWE-787 |
01 Jun 2026, 17:17
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
30 May 2026, 11:17
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.7 |
28 May 2026, 10:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-05-28 10:16
Updated : 2026-06-24 16:51
NVD link : CVE-2026-46123
Mitre link : CVE-2026-46123
CVE.ORG link : CVE-2026-46123
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-787
Out-of-bounds Write