{"id":"CVE-2026-98099","revision":"3c1e43feae2341cc8765349518e3f4ff","records":[{"revision":"3c1e43feae2341cc8765349518e3f4ff","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98099","aliases":[],"title":"ipv6: mcast: use rcu_assign_pointer() for __rcu list updates","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: use rcu_assign_pointer() for __rcu list updates\n\nSeveral places in net/ipv6/mcast.c update RCU-protected lists\n(np->ipv6_mc_list, idev->mc_list, idev->mc_tomb) using direct pointer\nassignments instead of rcu_assign_pointer():\n\n1. In __ipv6_dev_mc_dec(), unlinking a group from idev->mc_list did:\n       *map = ma->next;\n   without rcu_assign_pointer() while concurrent readers traverse\n   idev->mc_list locklessly under rcu_read_lock().\n2. In ipv6_sock_mc_drop() and __ipv6_sock_mc_close(), unlinking a group\n   from np->ipv6_mc_list directly assigned *lnk = mc_lst->next and\n   np->ipv6_mc_list = mc_lst->next without rcu_assign_pointer(), racing\n   with lockless readers in inet6_mc_check().\n3. In __ipv6_sock_mc_join(), mc_lst->next was initialized to\n   np->ipv6_mc_list via raw assignment before publishing mc_lst.\n4. In mld_del_delrec() and __ipv6_dev_mc_inc(), __rcu source pointers\n   passed into rcu_assign_pointer() lacked explicit dereference helpers.\n\nFix these by consistently using rcu_assign_pointer() along with\nmc_dereference() / sock_dereference().","state":0,"publishedAt":"2026-09-25T10:24:28.929+00:00","modifiedAt":"2026-10-21T12:54:29.854+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv6/mcast.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"456b61bca8ee324ab6c18b065e632c9a8c88aa39\",\n                            \"lessThan\": \"0e3e3cec28c4d1bf29948da40b4e9e5d44f7852b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"456b61bca8ee324ab6c18b065e632c9a8c88aa39\",\n                            \"lessThan\": \"49d7e1b456ba2f3ee08b3e264d999c09992cde8e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"456b61bca8ee324ab6c18b065e632c9a8c88aa39\",\n                            \"lessThan\": \"afca229b39acc2590976b3e4f6e0fe76cededc60\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"456b61bca8ee324ab6c18b065e632c9a8c88aa39\",\n                            \"lessThan\": \"2e46b0c9fcf7e10b64ce1630b925f47918d1f7f6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"456b61bca8ee324ab6c18b065e632c9a8c88aa39\",\n                            \"lessThan\": \"0c8f56c583c3250408367880c98e4d6fbc929315\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv6/mcast.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.38\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.38\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.160\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.114\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.57\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.7\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/0e3e3cec28c4d1bf29948da40b4e9e5d44f7852b","https://git.kernel.org/stable/c/49d7e1b456ba2f3ee08b3e264d999c09992cde8e","https://git.kernel.org/stable/c/afca229b39acc2590976b3e4f6e0fe76cededc60","https://git.kernel.org/stable/c/2e46b0c9fcf7e10b64ce1630b925f47918d1f7f6","https://git.kernel.org/stable/c/0c8f56c583c3250408367880c98e4d6fbc929315"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98099","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98099","identifiers":["CVE-2026-98099"]},"retained":false,"historicalAffected":[]}],"coverage":[]}