CVE-2026-108952

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.

CVSS v3 4.6 MEDIUM

4.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.9 / Impact : 3.6

Attack Vector PHYSICAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/RT-Thread/rt-thread
https://github.com/RT-Thread/rt-thread/blob/99428a1e7f7447955aa860f7c969273a12095b8f/components/legacy/usb/usbdevice/class/cdc_vcom.c#L518
https://github.com/RT-Thread/rt-thread/commit/ceef6e0ccd646aef61b907aeb9f29269d1caba50
https://github.com/RT-Thread/rt-thread/issues/11739
https://github.com/RT-Thread/rt-thread/pull/11770
https://www.vulncheck.com/advisories/rt-thread-through-5.3.0-memory-corruption-via-usb-cdc-vcom-driver

Configurations

No configuration.

History

12 Oct 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 13:17

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108952

Mitre link : CVE-2026-108952

CVE.ORG link : CVE-2026-108952

JSON object : View

Products Affected

No product.

CWE

CWE-843

Access of Resource Using Incompatible Type ('Type Confusion')

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