CVE-2025-37799

A flaw was found in the Linux kernel's vmxnet3 network driver. When processing network packets using the eXpress Data Path (XDP), an incorrect packet size calculation causes transmitted network frames to be padded with uninitialized kernel memory. A remote network recipient or observer receiving these packets can inspect the residual data, leading to an information disclosure of sensitive kernel or payload information.

A bug in the vmxnet3 XDP path caused uninitialized kernel memory to be leaked into network packets, due to incorrect packet size handling. This results in a kernel memory disclosure to remote systems, affecting confidentiality but not system stability.

RHEL versions prior to 9.5 are not affected by this vulnerability, as the vulnerable code is not present in those releases.

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.

To mitigate this issue, prevent module vmxnet3 from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.