CVE-2026-74508: Linux

High severity, CVSS 8.8. EPSS: 0.4% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: HIDP: reject frames without a transaction header hidp_recv_ctrl_frame() and hidp_recv_intr_frame() read skb->data[0] before checking that the L2CAP SDU contains a transaction header. A connected HIDP peer can send an empty basic-mode SDU and make both paths use an uninitialized byte from skb tailroom. KMSAN reports the use in hidp_session_run(), with the uninitialized value originating in __alloc_skb() through vhci_write(). The control path produces two reports and the interrupt path produces one. The byte can also be controlled by a malformed lower-layer packet. If an HCI ACL packet contains an L2CAP PDU with a declared zero-length payload followed by an extra 0x15 byte, l2cap_recv_acldata() reduces skb->len to the declared PDU length before dispatch. The current HIDP path nevertheless consumes the extra byte as HIDP_TRANS_HID_CONTROL | HIDP_CTRL_VIRTUAL_CABLE_UNPLUG and terminates the HIDP session. With this change, the same packet is discarded and a subsequent feature report request succeeds. Pull the transaction header with skb_pull_data() and discard frames that do not contain it.

Affected products

• Linux Linux: from 2.6.12, before 5.10.266 (fixed in 5.10.266); from 5.11, before 5.15.216 (fixed in 5.15.216); from 5.16, before 6.1.183 (fixed in 6.1.183); from 6.2, before 6.6.151 (fixed in 6.6.151); from 6.7, before 6.12.103 (fixed in 6.12.103); from 6.13, before 6.18.44 (fixed in 6.18.44); …

Published 2026-08-15. Last modified 2026-08-23.