PT-2025-42748 · Linux+2 · Linux Kernel+2
Published
2025-08-23
·
Updated
2026-03-13
·
CVE-2025-40004
CVSS v2.0
4.6
Medium
| Vector | AV:L/AC:L/Au:S/C:N/I:N/A:C |
Name of the Vulnerable Software and Affected Versions
Linux kernel (affected versions not specified)
Description
A buffer overflow issue exists in the USB 9pfs transport layer. Inconsistent size validation between packet header parsing and actual data copying allows a malicious USB host to overflow heap buffers. The vulnerability occurs because
usb9pfs rx header() validates only the declared size in the packet header, while usb9pfs rx complete() uses req->actual (actual received bytes) for memcpy. This discrepancy allows an attacker to create packets with a small declared size, bypassing validation, but with a large actual payload, triggering an overflow during the memcpy operation. The vulnerable functions are usb9pfs rx header() and usb9pfs rx complete(). The variable req->actual is used in the vulnerable memcpy operation.Recommendations
At the moment, there is no information about a newer version that contains a fix for this vulnerability.
Exploit
Buffer Overflow
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Weakness Enumeration
Related Identifiers
Affected Products
Linuxmint
Linux Kernel
Ubuntu