Multicast Query Vulnerability in Linux Kernel Network Bridge Module

CVE-2025-39773

What is CVE-2025-39773?

A vulnerability exists in the Linux kernel's network bridge module, specifically related to multicast querying. When the multicast_query_interval is set to an excessively high value, it can lead to an overflow in the local 'time' variable during the br_multicast_send_query() execution. This overflow may cause a timer to expire prematurely, creating a loop that results in a soft lockup condition within the system. System administrators should be aware of this issue as it can significantly impact system performance and stability.

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