CVE-2025-21758

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A vulnerability in the Linux kernel has been resolved. The issue is related to the mld newpack() function, which can be called without proper synchronization, specifically without holding RTNL or RCU protection. This function is used in the context of IPv6 multicast. The problem arises because ipv6.igmp sk uses GFP KERNEL allocations, which can sleep, making it incompatible with sock alloc send skb(). As a result, alloc skb() is used instead, and the net->ipv6.igmp sk socket is charged under RCU protection.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.