CVE-2026-15890
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk0th percentile - higher than 0% of all known CVEs
Summary
A vulnerability in the PSA Internal Trusted Storage module in Zephyr involves a lack of synchronization in nonce generation for AEAD encryption. The function secure_storage_its_transform_aead_get_nonce() uses unsynchronized function-local static variables, and concurrent writes to the same UID can lead to nonce reuse with the same key. This causes a catastrophic AEAD failure, enabling data leakage and forgery of stored entries.
Risk Assessment
The organization is at risk of exposure of sensitive data stored in ITS, including PSA keys, and potential forgery of entries by an attacker with access to raw flash storage. Nonce reuse in AES-GCM or ChaCha20-Poly1305 leads to plaintext XOR leakage and, for GCM, exposes the authentication key.
Recommendation
It is recommended to immediately apply the fix provided by Zephyr, which adds a mutex (K_MUTEX_DEFINE) around nonce generation. Additionally, avoid concurrent writes to the same UID from multiple threads in applications until the patch is deployed.
Other vulnerabilities in Zephyr
See all- CVE-2026-10772Unknown
This CVE has been rejected as a duplicate. The described vulnerability involved incorrect permission checking in the Bluetooth GATT notify/indicate paths in the Zephyr stack, but was already reported as CVE-2026-2411.
- CVE-2026-10676Unknown
CVE-2026-10676 has been withdrawn as analysis determined that the reported defect is not reachable in any released version of Zephyr. In every supported release, the affected value is corrected before use.
- CVE-2026-5067Critical
Zephyr OS has a memory corruption vulnerability in the HTTP server WebSocket upgrade path. An unauthenticated remote attacker can trigger it by sending a crafted Sec-WebSocket-Key header. The bounded copy does not guarantee NUL termination, leading to out-of-bounds read/write on stack.
- CVE-2026-17050Medium
The experimental USB host stack in Zephyr contains a double-free vulnerability in the configuration descriptor buffer. On three error paths, the buffer is freed but the pointer is left dangling, leading to a second free during cleanup. The vulnerability can be triggered by a malicious or malformed USB device.
- CVE-2026-16515Medium
The net_icmpv6_send_error() function in the Zephyr network stack implemented only one of the three RFC 4443 section 2.4 suppression rules, so it did not check whether the packet's source address identifies a single node or whether the packet was sent to a multicast destination. An unauthenticated attacker on the same link can send a single IPv6 packet to ff02::1 with a spoofed victim source, causing every Zephyr node to emit ICMPv6 Parameter Problem messages to that victim (reflection with amplification), or send a unicast packet with a multicast source address, turning it into a link-flooding multicast frame.
- CVE-2026-15924Medium
Zephyr's TLS socket layer (subsys/net/lib/sockets/sockets_tls.c) keeps a process-global client_cache array of cached client session buffers shared by every TLS socket, with access serialized only by the per-socket ctx->lock mutex. Because CONFIG_NET_SOCKETS_TLS_MAX_CLIENT_SESSION_COUNT defaults to 1, two concurrent client sockets contend for the same slot, causing a use-after-free read and a double-free when two saves evict the same entry. This corrupts the mbedTLS heap; the fix adds a dedicated session_cache_lock mutex taken across every accessor of client_cache.
- CVE-2026-15923Medium
The Zephyr SDIO subsystem has a vulnerability in sdio_io_rw_extended_helper() where func->cis.max_blk_size is decoded from the SDIO card without validation. If a card reports a maximum block size of zero, the transfer loop never terminates, causing a thread hang and permanent mutex lock, leading to denial of service for the SDIO peripheral.
- CVE-2026-15460Medium
A vulnerability in the Bluetooth Classic (BR/EDR) stack in Zephyr RTOS affects the L2CAP receive handler, which dispatches inbound data PDUs based only on the destination channel ID without verifying that the channel has reached the BT_L2CAP_CONNECTED state. An attacker within radio range can send data to a channel during connection setup, before configuration and authentication complete. This can lead to delivery of attacker data to upper-layer protocols on a half-open channel and to use of stale or partially initialized channel state, causing denial of service or a potential dangling-pointer condition.
- CVE-2026-14697Medium
In the IPv6 subsystem of the Zephyr stack (subsys/net/ip/ipv6_nbr.c), the net_ipv6_send_ns() function allocates a transmit net_pkt for a Neighbor Solicitation. When called with a data packet pending on an unresolved neighbor and the neighbor's pending_queue is already non-empty, the function appends the data packet and returns early without sending the NS via net_send_data() or releasing it with net_pkt_unref(). The freshly allocated NS net_pkt and its attached TX buffers are held only by a local variable and are leaked permanently, never returning to CONFIG_NET_PKT_TX_COUNT / CONFIG_NET_BUF_TX_COUNT.
- CVE-2026-13735Low
Zephyr's WireGuard implementation mishandled keepalive packets. A type-4 message with a 16-byte payload (empty plaintext plus Poly1305 tag) was accepted without tag verification because wg_process_data_message() returned early before calling wg_decrypt_packet(). An attacker could send a forged keepalive without knowing the session key.
Original NVD description (English source)
The default AEAD nonce provider for the PSA Internal Trusted Storage transform module, secure_storage_its_transform_aead_get_nonce() in subsys/secure_storage/src/its/transform/aead_get.c, stores its nonce counter in unsynchronized function-local static variables (s_nonce and s_nonce_initialized). Every ITS write obtains its AES-GCM or ChaCha20-Poly1305 nonce here via secure_storage_its_transform_to_store(). Because the function held no lock, two threads calling it concurrently race on the shared statics: the initialization path (psa_generate_random() followed by memcpy()) and the non-atomic increment-then-copy path can each hand the same nonce value to two distinct encryption operations, and can lose increments so the counter repeats values it was designed never to repeat. The ITS layer (secure_storage_its_set() in subsys/secure_storage/src/its/implementation.c) performs no serialization of its own, so concurrent same-UID writes reach the racy provider directly. Reusing a nonce with the same key under AES-GCM or ChaCha20-Poly1305 is a catastrophic AEAD failure: it leaks the XOR of the two plaintexts (ITS routinely stores secrets, including PSA persistent keys) and, for GCM, exposes the authentication key, enabling forgery of stored entries. Because the AEAD key is derived per entry UID, the security-relevant collision is two concurrent writes to the same UID both receiving the same nonce; an adversary able to read the raw backing storage can then exploit the reuse. Both ITS store back-ends shipped with Zephyr, zms.c and the settings/NVS back-end in settings.c, are log-structured flash stores with deferred garbage collection, so an entry superseded by a rewrite remains physically present in the partition until its sector is reclaimed. Two same-UID writes that race therefore leave both ciphertexts readable in the raw image at once, which is the condition the nonce reuse needs to be exploitable. The trigger remains narrow: both built-in key providers (DEVICE_ID_HASH and ENTRY_UID_HASH) salt the derived key with the entry UID, so reuse across different UIDs is harmless, and the exposure requires an application that writes the same UID concurrently from two threads. The fix serializes the provider with a K_MUTEX_DEFINE(s_nonce_mutex) held for the duration of nonce generation.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS