CVE-2025-22104 is a vulnerability identified in the Linux kernel's ibmvnic driver, which is used for IBM virtual network interface cards. The issue arises from improper handling of hex dump printing within the driver. Specifically, the driver previously cast the buffer to an 8-byte long and printed it using string formatters without ensuring the buffer size was a multiple of 8. This led to a read buffer overflow condition when the buffer size was not aligned to 8 bytes. The vulnerability was detected through Kernel Address Sanitizer (KASAN) reports indicating slab-out-of-bounds reads during the ibmvnic_login function execution. The root cause is that the driver reads beyond the allocated buffer boundary, potentially exposing kernel memory contents or causing kernel instability. The patch introduced a new ibmvnic function that iterates over the buffer and uses the kernel helper function hex_dump_to_buffer, which safely handles arbitrary buffer sizes and prevents out-of-bounds reads. This vulnerability affects specific Linux kernel versions identified by commit hashes, and no known exploits are currently reported in the wild. The vulnerability does not require user interaction or authentication to be triggered but depends on the presence of the ibmvnic driver and its usage in the environment.

For European organizations, the impact of CVE-2025-22104 primarily concerns systems running Linux kernels with the vulnerable ibmvnic driver enabled, typically on IBM virtualized environments or hardware that uses IBM virtual network interfaces. Successful exploitation could lead to kernel memory disclosure or instability, potentially allowing attackers to glean sensitive information from kernel memory or cause denial of service through kernel crashes. While this vulnerability is a read overflow rather than a write overflow, the exposure of kernel memory could aid attackers in further privilege escalation or lateral movement within the network. Organizations relying on IBM virtualized infrastructure or cloud services that use IBM hardware and Linux kernels are at higher risk. The vulnerability could affect data confidentiality and system availability, especially in critical infrastructure or data centers. Given the lack of known exploits, the immediate risk is moderate, but the potential for future exploitation exists if attackers develop reliable attack vectors.

European organizations should prioritize patching Linux kernels to versions that include the fix for CVE-2025-22104. Specifically, they should update to kernel releases that incorporate the new ibmvnic function using hex_dump_to_buffer to prevent out-of-bounds reads. System administrators should audit their environments to identify systems running the ibmvnic driver, particularly on IBM virtualized platforms. If immediate patching is not feasible, organizations can consider disabling the ibmvnic driver if it is not essential to operations, though this may impact network functionality on IBM virtualized hardware. Monitoring kernel logs for KASAN or related error messages can help detect attempts to trigger the vulnerability. Additionally, implementing strict access controls to limit untrusted user or process access to vulnerable systems reduces the attack surface. Organizations should also maintain up-to-date intrusion detection systems capable of recognizing anomalous kernel behavior indicative of exploitation attempts.