Zephyr: The RTIO streaming completion callback adxl345_process_fifo_samples_cb() in
Affects zephyrSource GCVE Database
Not known to be exploited · CVSS 3.6 Low.
Data as of 28 Oct 2026, 22:28 UTC
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 23 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10zephyrpkg:deb/ubuntu/zephyr?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSzephyrpkg:deb/ubuntu/zephyr?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSzephyrpkg:deb/ubuntu/zephyr?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSzephyrpkg:deb/ubuntu/zephyr?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSzephyrpkg:deb/ubuntu/zephyr?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 18.04 LTSzephyrpkg:deb/ubuntu/zephyr?arch=source&distro=bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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. A 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. The 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.
References
- ubuntu.com/security/CVE-2026-79978 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-79978 (opens in a new tab)
- github.com/zephyrproject-rtos/zephyr/commit/3451bb1e1e9165844060551164adb8a756e7b6b7 (opens in a new tab)
- github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-4v56-r4qm-v964 (opens in a new tab)