{"id":"CVE-2026-108952","state":"PUBLISHED","title":"RT-Thread through 5.3.0 Memory Corruption via USB CDC VCOM Driver","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.","publishedAt":"2026-10-12T12:13:04.800Z","updatedAt":"2026-10-13T14:59:23.750Z","severity":{"score":5.1,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["RT-Thread rt-thread"],"affected":[{"vendor":"RT-Thread","product":"rt-thread","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"5.3.0","versionType":"semver"}]}],"references":["https://github.com/RT-Thread/rt-thread/issues/11739","https://github.com/RT-Thread/rt-thread/pull/11770","https://github.com/RT-Thread/rt-thread/commit/ceef6e0ccd646aef61b907aeb9f29269d1caba50","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","https://www.vulncheck.com/advisories/rt-thread-through-5.3.0-memory-corruption-via-usb-cdc-vcom-driver"],"weaknesses":["CWE-843"],"ingestedAt":"2026-10-29T20:10:33.477Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/108xxx/CVE-2026-108952.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-108952","state":"PUBLISHED","datePublished":"2026-10-12T12:13:04.800Z","dateUpdated":"2026-10-13T14:59:23.750Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-10-11T19:04:35.513Z"},"containers":{"cna":{"title":"RT-Thread through 5.3.0 Memory Corruption via USB CDC VCOM Driver","descriptions":[{"lang":"en","value":"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(). 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