CVE-2026-15890 AEAD nonce reuse in Zephyr secure_storage ITS default nonce provider due to missing thread synchronization

The default AEAD nonce provider for the PSA Internal Trusted Storage transform module, securestorageitstransformaeadgetnonce in subsys/securestorage/src/its/transform/aeadget.c, stores its nonce counter in unsynchronized function-local static variables snonce and snonceinitialized. Every ITS writ...