CVE-2026-108952 RT-Thread through 5.3.0 Memory Corruption via USB CDC VCOM Driver
A memory corruption flaw in the RT-Thread USB CDC driver allows a connected host to cause denial of service via buffer overflow and invalid free.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-108952?
CVE-2026-108952 is a medium-severity memory corruption vulnerability in rt-thread, published on 12 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
RT-Thread through 5.3.0 contains a memory corruption vulnerability in the legacy USB CDC virtual COM port driver that aliases rx_ringbuffer as a Serial V2 rt_serial_rx_fifo in _function_enable(). A connected USB host configuring the CDC device triggers writes past the ring buffer into struct vcom members and an invalid rt_free() on close, causing denial of service.
Weakness: CWE-843
Which versions are affected by CVE-2026-108952?
How do I fix CVE-2026-108952?
No fix has been published for CVE-2026-108952 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-108952 being exploited?
There is no known exploitation of CVE-2026-108952 in the wild and no public exploit code.
Sources
Also known as GHSA-x4hq-c3c6-m368.