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TI-2026-70947 Aliases CVE-2026-108952GHSA-x4hq-c3c6-m368

Type confusion in RT-Thread USB CDC VCOM driver corrupts memory

Priority LOW 23CWE-843Published · Updated

Key facts

Attack vector
Physical
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-843 and the CVSS impact.

Summary

RT-Thread through 5.3.0 contains a memory corruption flaw in its legacy USB CDC virtual COM port driver, where the rx_ringbuffer is treated as an incompatible Serial V2 receive FIFO type (CWE-843). A connected USB host that configures the CDC device causes writes past the ring buffer into struct vcom members and an invalid free on close, leading to denial of service. The source describes the attack as requiring only a connected USB host, with no privileges or user interaction.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00201 10th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
RT-Threadrt-threadup to 5.3.0—No fix listedCNA
  • rt-thread VendorRT-Thread Affected up to 5.3.0 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for rt-thread.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Timeline

  1. 2026-10-12 Threatist record created from CVE-2026-108952
  2. 2026-10-12 Alias added: GHSA-x4hq-c3c6-m368
  3. 2026-10-13 CISA SSVC decision points changed

References

Patch 2

Other 3

  • TI-2024-16722 A buffer overflow occurs in utilities/rt-link/src/rtlink.c in RT-Thread through 5.0.2. CVSS 3.1HIGH 8.8
  • TI-2025-05294 RT-Thread lwp_syscall.c sys_sigprocmask array index CVSS 4.0HIGH 8.6
  • TI-2025-05293 RT-Thread Parameter lwp_syscall.c sys_select memory corruption CVSS 4.0HIGH 8.6
  • TI-2024-16718 A stack buffer overflow occurs in libc/posix/ipc/mqueue.c in RT-Thread through 5.0.2. CVSS 3.1HIGH 8.4
  • TI-2024-16717 A heap buffer overflow occurs in finsh/msh_file.c and finsh/msh.c in RT-Thread through 5.0.2. CVSS 3.1HIGH 8.4
  • TI-2024-16715 drivers/wlan/wlan_mgmt,c in RT-Thread through 5.0.2 has an integer signedness error and resultant buffer overflow. CVSS 3.1HIGH 8.4
See all 17 →

Sources

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