Is CVE-2026-108952 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-108952 being exploited in the wild.

How severe is CVE-2026-108952?

Medium severity, with a CVSS score of 4.6, published 12 October 2026.

Is there a fix for CVE-2026-108952?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-108952 attacked?

It is attacked from the adjacent network.

Am I affected by CVE-2026-108952?

Check whether you run RT-Thread at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-108952: RT-Thread USB CDC memory corruption in ring buffer

CVE-2026-108952 · Severity: medium · CVSS 4.6 · Published 2026-10-12

RT-Thread is an open-source real-time operating system used in IoT embedded devices. A USB CDC (Communications Device Class) driver in versions through 5.3.0 has a memory corruption flaw that allows a connected USB host to write data past buffer boundaries and trigger invalid memory operations. This can crash the device, causing denial of service and potentially allowing code execution on vulnerable systems.

Technologies: RT-Thread. Vendors: RT-Thread.

Quick answers

Is CVE-2026-108952 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-108952 being exploited in the wild.
How severe is CVE-2026-108952?: Medium severity, with a CVSS score of 4.6, published 12 October 2026.
Which products and versions are affected?: RT-Thread through 5.3.0.
Is there a fix for CVE-2026-108952?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-108952 attacked?: It is attacked from the adjacent network.
Am I affected by CVE-2026-108952?: Check whether you run RT-Thread at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The legacy USB CDC virtual COM port driver incorrectly aliases the rx_ringbuffer as an rt_serial_rx_fifo structure in the _function_enable() function. When a USB host configures the CDC device, attacker-controlled writes overflow the ring buffer into adjacent vcom structure members and cause an invalid rt_free() call on close, leading to memory corruption and denial of service.

Affected products

RT-Thread RT-Thread through 5.3.0

Timeline

2026-10-12: disclosed

References

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