CVE-2025-55095 Denial of service in Eclipse ThreadX - USBX
A malicious USB mass storage device can cause a stack overflow and denial of service in Eclipse ThreadX USBX due to unbounded recursion in partition mounting.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-55095?
CVE-2025-55095 is a medium-severity denial of service vulnerability in Eclipse ThreadX - USBX, published on 27 Jan 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
The function _ux_host_class_storage_media_mount() is responsible for mounting partitions on a USB mass storage device. When it encounters an extended partition entry in the partition table, it recursively calls itself to mount the next logical partition.
This recursion occurs in _ux_host_class_storage_partition_read(), which parses up to four partition entries. If an extended partition is found (with type UX_HOST_CLASS_STORAGE_PARTITION_EXTENDED or EXTENDED_LBA_MAPPED), the code invokes: _ux_host_class_storage_media_mount(storage, sector + _ux_utility_long_get(...));
There is no limit on the recursion depth or tracking of visited sectors. As a result, a malicious or malformed disk image can include cyclic or excessively deep chains of extended partitions, causing the function to recurse until stack overflow occurs.
Which versions are affected by CVE-2025-55095?
It affects 1 product.
Products include Eclipse Threadx Usbx.
How do I fix CVE-2025-55095?
No fix has been published for CVE-2025-55095 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-55095 being exploited?
There is no known exploitation of CVE-2025-55095 in the wild and no public exploit code.
Other vulnerabilities in Eclipse ThreadX - USBX
- CVE-2022-29246 Potential buffer overflow in function DFU upload in Azure RTOS USBX
- CVE-2022-39293 Azure RTOS USBX Host PIMA vulnerable to read integer underflow with buffer overflow
- CVE-2022-36063 USBX Host CDC ECM integer underflow with buffer overflow
- CVE-2022-29223 Buffer overflow on HUB descriptor in Azure RTOS USBX
- CVE-2023-48695 Azure RTOS USBX Remote Code Execution Vulnerability
Sources
Also known as GHSA-qfmp-wch9-rpv2.