CVE-2026-108952 (GCVE-0-2026-108952)
Vulnerability from cvelistv5 – Published: 2026-10-12 12:13 – Updated: 2026-10-13 14:59
VLAI
EPSS
VEX
Title
RT-Thread through 5.3.0 Memory Corruption via USB CDC VCOM Driver
Summary
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.
Severity
4.6 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-13 14:58 UTC
CWE
- CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://github.com/RT-Thread/rt-thread/issues/11739 | issue-tracking |
| https://github.com/RT-Thread/rt-thread/pull/11770 | issue-trackingpatch |
| https://github.com/RT-Thread/rt-thread/commit/cee… | patch |
| https://github.com/RT-Thread/rt-thread/blob/99428… | technical-description |
| https://github.com/RT-Thread/rt-thread | product |
| https://www.vulncheck.com/advisories/rt-thread-th… | third-party-advisory |
Impacted products
Date Public
2026-08-23 00:00
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