CVE-2026-10655 Use-after-free race in SNTP async client when closing the socket while the socket service is still polling it

The asynchronous SNTP client in Zephyr subsys/net/lib/sntp/sntp.c, sntpcloseasync closed the UDP socket file descriptor directly from the calling thread immediately after detaching it from the network socket service, without synchronizing with the socket-service poll thread. The socket service...

CVE-2026-10655

Concrete details found: Zephyr’s asynchronous SNTP client (sntp_close_async) can race with the socket service poll thread. Closing the UDP socket descriptor from a different thread (SNTP timeout path) may free and reuse net_context while the poll thread holds a poller node, causing a use-after-fr...