CVE-2025-21743

In the Linux kernel, the following vulnerability has been resolved:

usbnet: ipheth: fix possible overflow in DPE length check

Originally, it was possible for the DPE length check to overflow if wDatagramIndex + wDatagramLength > U16_MAX. This could lead to an OoB read.

Move the wDatagramIndex term to the other side of the inequality.

An existing condition ensures that wDatagramIndex < urb->actual_length.

This vulnerability is rated as Moderate impact for Red Hat Enterprise Linux because exploitation requires physical access to attach a malicious USB device or administrative access to an emulated USB interface in virtualized environments. An integer overflow in the Apple iPhone USB Ethernet (ipheth) driver's packet descriptor handling can cause an out-of-bounds memory read, potentially leading to a kernel crash or local information leakage. Standard enterprise server deployments do not typically utilize USB network tethering, which substantially limits real-world exposure.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.