CVE-2026-98025

A flaw was found in the Linux kernel's cx82310_eth USB Ethernet driver. An attacker connecting a malicious USB device can trigger a heap-based buffer overflow by sending crafted packets containing a reboot indicator. Because the driver fails to discard the packet after detecting the reboot signal, it bypasses packet size checks and writes data beyond allocated memory bounds. This issue can cause a system crash, leading to a Denial of Service (DoS), or potentially allow arbitrary code execution with kernel privileges.

A heap based buffer overflow in the cx82310_eth USB Ethernet driver occurs because a 0xffff router reboot sentinel schedules reenable work but then falls through into incomplete packet handling. A controlled CX82310 device can send a 4096 byte USB receive buffer beginning with ff ff, causing up to 4094 bytes to be copied into a partial_data buffer allocated for only 1516 bytes. Later processing also reads beyond the partial buffer and the next receive buffer while constructing a malformed large frame. For the CVSS the PR:N metric is used because an attacker only needs control of the connected USB networking device and does not need a local account or code execution on the host. The attack vector is physical AV:P and the issue is not directly network reachable. Impact is at least denial of service through kernel memory corruption and may include confidentiality integrity impact or privilege escalation if the controlled heap overflow can be developed into a reliable kernel exploitation primitive. In practice exploitation requires physical access to attach a malicious device or prior compromise of an already attached USB router or network adapter.

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.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.