{"id":"CVE-2026-74255","revision":"4213d13b9b4f4ab4bba34cb38e4b45af","records":[{"revision":"4213d13b9b4f4ab4bba34cb38e4b45af","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-74255","aliases":[],"title":"tipc: fix UAF in tipc_l2_send_msg()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix UAF in tipc_l2_send_msg()\n\nSyzbot reported a slab-use-after-free in ipvlan_hard_header() when\ncalled from tipc_l2_send_msg().\n\nThe root cause is that tipc_disable_l2_media() calls synchronize_net()\nwhile b->media_ptr is still valid. This allows concurrent RCU readers\nto obtain the device pointer after synchronize_net() has finished.\nThe pointer is cleared later in bearer_disable(), but without any\nsubsequent synchronization, allowing the device to be freed while\nstill in use by readers.\n\nFix this by clearing b->media_ptr in tipc_disable_l2_media() before\ncalling synchronize_net().\n\nThis is safe to do now because the call order in bearer_disable()\nwas reversed in 0d051bf93c06 (\"tipc: make bearer packet filtering generic\")\nto call tipc_node_delete_links() (which needs the pointer) before\ndisable_media().\n\nhttps: //lore.kernel.org/netdev/6a2c1007.428ffe26.258b27.015d.GAE@google.com/T/#u","state":0,"publishedAt":"2026-08-15T05:57:34.293+00:00","modifiedAt":"2026-10-16T18:55:27.929+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/tipc/bearer.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"609ced2301be1df7e7ed2ef47d1d916674e6ba3b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"71aafa16d79b107b33837f60b6cbc7d0cb8c5708\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"f4002f1c669cc02e3763f479fc25ff1dfa9e2420\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"50ff092633b06382e5091dd5b093ce943d4ac2f9\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"aef12b5ce793dea6b3a97a58fd0f946000ae8945\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"0d8a12d7143126afdf9fbe2e3d438650dd6603ed\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"35e0297a93c3c34a3924eeef816c03504e3ab5c5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"282b3a056225b35024246f63feb91d769d714dad\",\n                            \"lessThan\": \"f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6\",\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/tipc/bearer.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.4\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.4\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.261\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.212\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.178\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.145\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.97\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.40\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.5\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/609ced2301be1df7e7ed2ef47d1d916674e6ba3b","https://git.kernel.org/stable/c/71aafa16d79b107b33837f60b6cbc7d0cb8c5708","https://git.kernel.org/stable/c/f4002f1c669cc02e3763f479fc25ff1dfa9e2420","https://git.kernel.org/stable/c/50ff092633b06382e5091dd5b093ce943d4ac2f9","https://git.kernel.org/stable/c/aef12b5ce793dea6b3a97a58fd0f946000ae8945","https://git.kernel.org/stable/c/0d8a12d7143126afdf9fbe2e3d438650dd6603ed","https://git.kernel.org/stable/c/35e0297a93c3c34a3924eeef816c03504e3ab5c5","https://git.kernel.org/stable/c/f4c3d89fc986b0da196ddfc6cfe0ea5d5d08bec6"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74255","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-74255","identifiers":["CVE-2026-74255"]},"retained":false,"historicalAffected":[]}],"coverage":[]}