{"id":"CVE-2025-39764","state":"PUBLISHED","title":"netfilter: ctnetlink: remove refcounting in expectation dumpers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ctnetlink: remove refcounting in expectation dumpers\n\nSame pattern as previous patch: do not keep the expectation object\nalive via refcount, only store a cookie value and then use that\nas the skip hint for dump resumption.\n\nAFAICS this has the same issue as the one resolved in the conntrack\ndumper, when we do\n  if (!refcount_inc_not_zero(&exp->use))\n\nto increment the refcount, there is a chance that exp == last, which\ncauses a double-increment of the refcount and subsequent memory leak.","publishedAt":"2025-09-11T16:52:32.060Z","updatedAt":"2026-10-15T01:08:12.652Z","severity":null,"assigner":"Linux","products":["Linux 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