{"id":"CVE-2026-79978","revision":"9afdcc35f5fe4a7bb0e65c7ede5e1c34","records":[{"revision":"9afdcc35f5fe4a7bb0e65c7ede5e1c34","observedAt":"2026-10-23T20:48:20.645+00:00","statement":{"source":"cve-program","id":"CVE-2026-79978","aliases":[],"title":"Out-of-bounds write in the ADXL345 sensor driver RTIO streaming FIFO read path","description":"The RTIO streaming completion callback adxl345_process_fifo_samples_cb() in drivers/sensor/adi/adxl345/adxl345_stream.c clamps the amount of FIFO data it will report (read_len = MIN(fifo_bytes, buf_avail)) to the space actually returned by rtio_sqe_rx_buf(), but then queues one 6-byte bus read per hardware FIFO entry at consecutive offsets from read_buf, bounded by the device-reported entry count rather than by the clamp. When the allocated buffer is smaller than a full batch, the driver writes up to 186 bytes past the end of the allocation; a companion defect left data->fifo_total_bytes un-reset at batch start, so an aborted or errored chain could leave a stale write offset that pushes the next batch's writes out of bounds as well.\n\nA short buffer is an expected, first-class outcome of the RTIO allocator: rtio_block_pool_alloc() walks the requested size down one block at a time until a contiguous run is available, and the driver only demands sizeof(struct adxl345_fifo_data) + 6 bytes as its minimum. Any streaming configuration whose mempool block granularity is smaller than a full FIFO batch (204 bytes) — for example the sensor shell's RTIO_DEFINE_WITH_MEMPOOL(sensor_read_rtio, 8, 8, 32, 64, 4) used by sensor stream <dev> on fifo_wm incl, or the 16-byte-block streaming example in the documentation — takes this path whenever the pool is fragmented or the consuming thread falls behind.\n\nThe out-of-bounds writes are performed by the I2C/SPI RTIO backend (DMA on many SoCs) into the shared RTIO block pool, corrupting neighbouring live buffers or, for a pool smaller than one batch, memory beyond the pool itself. The written bytes are accelerometer samples and the destination follows the allocation, so there is no controllable corruption primitive: the realistic impact is silent corruption of other RTIO consumers' data or a crash. Reaching it requires a board with an interrupt-wired ADXL345 built with CONFIG_ADXL345_STREAM, plus buffer-pool starvation, which a co-resident local workload can induce but which also occurs spontaneously under load; there is no network, USB or radio path to this code.","state":0,"publishedAt":"2026-10-23T19:56:14.995+00:00","modifiedAt":"2026-10-23T19:56:14.995+00:00","affected":[{"ecosystem":"https://github.com/zephyrproject-rtos/zephyr","name":"zephyr","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"zephyrproject\",\n                    \"product\": \"zephyr\",\n                    \"collectionURL\": \"https://github.com/zephyrproject-rtos/zephyr\",\n                    \"packageName\": \"zephyr\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"programFiles\": [\n                        \"drivers/sensor/adi/adxl345/adxl345_stream.c\"\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"adxl345_process_fifo_samples_cb\"\n                        }\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.0.0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\",\n                            \"lessThanOrEqual\": \"4.4.2\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L","score":3.6,"severity":"LOW"}],"references":["https://github.com/zephyrproject-rtos/zephyr/commit/3451bb1e1e9165844060551164adb8a756e7b6b7","https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-4v56-r4qm-v964"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-79978","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-79978","identifiers":["CVE-2026-79978"]},"retained":false,"historicalAffected":[]}],"coverage":[]}