SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2025-55095

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.

HIGH 7.0EPSS 0.14%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.14%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
7.0 HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.14% probability · 4th percentile
CISA KEV
Not listed
Weakness
CWE-121, CWE-674, CWE-787
Affected
eclipse/threadx usbx
Source
emo@eclipse.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.