CVE-2026-31641

A flaw was found in the Linux kernel's rxrpc subsystem. An unprivileged local user could exploit an integer overflow vulnerability in the rxrpc_preparse_xdr_yfs_rxgk() function. This flaw occurs when processing specially crafted key and ticket lengths, causing an incorrect memory allocation size. Consequently, a heap buffer overflow can occur, potentially leading to arbitrary code execution or a denial of service.

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.

The rxrpc kernel module can be prevented from loading to mitigate this issue. This action may impact applications that rely on the rxrpc protocol. To blacklist the rxrpc module:

1. Create a file /etc/modprobe.d/blacklist-rxrpc.conf with the following content:

   blacklist rxrpc
   install rxrpc /bin/true
   

2. Regenerate the initramfs:

   dracut -f -v
   

3. Reboot the system for the changes to take effect.