Vulnerability · Published Jun 28, 2026 · Assigned by zephyr
CVE-2026-10593Remotely triggerable NULL-pointer dereference in Bluetooth LE Audio BAP unicast client QoS-state handling
Medium 6.5
In plain English
A medium-severity null pointer dereference in zephyr from zephyrproject. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).
Official description
The Zephyr Bluetooth LE Audio Basic Audio Profile (BAP) unicast client mishandles peer-supplied ASE state notifications. In unicast_client_ep_qos_state() (subsys/bluetooth/audio/bap_unicast_client.c), the handler writes attacker-controlled QoS fields (interval, framing, phy, sdu, rtn, latency, pd) through the stream->qos pointer with only a stream != NULL guard. stream->qos is NULL for any stream that has been codec-configured via bt_bap_stream_config() but not yet added to a unicast group (it is set only by unicast_group_add_stream()). A malicious or buggy remote ASCS server, to which the local device is connected as a BAP unicast client, can send a GATT notification announcing the ASE has entered the QoS Configured state while the local endpoint is still in the Codec Configured state — a transition the dispatcher explicitly permits — during that window, causing a write through a NULL pointer and a crash (denial of service). The data written is itself remote-controlled. The defect shipped in v4.3.0 and v4.4.0 (and earlier). The fix re-points all BAP QoS storage to the always-valid embedded ep->qos struct, eliminating the NULL dereference.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| zephyrproject | zephyr | 4.3.0 – before 4.5.0 |
Weakness: CWE-476 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H