Kernel Memory Leak Vulnerability in Linux Kernel by Vendor

CVE-2025-40279

What is CVE-2025-40279?

The Linux Kernel vulnerability involves a memory leak in the networking component, specifically within the tcf_connmark_dump() function. The variable 'opt' was only partially initialized, which resulted in uninitialized padding bytes being leaked to userspace during netlink message copying. This flaw underscores the need for proper initialization practices, such as using memset, to ensure that all members and padding in a structure are cleared before usage, thereby preventing potential data exposure to unauthorized users.

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