{"id":"CVE-2026-74395","title":"RDMA/mlx5: Fix devx subscribe-event unwind NULL dereference","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/mlx5: Fix devx subscribe-event unwind NULL dereference\n\nMLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT() links event_sub into sub_list\nbefore initializing the fields used by …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 6e15b770461eeaa0ff73934922cb670a6a9db04e","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 9be9aca28424228586fe9211c373ebdb826ebb6c","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < f345e744b6b087188cde2377da5cbe9713b61353","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 1025dc2f7ba29b04b8687790fa91f9cd1a53141e","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 7921821fc2b19c01588311f6e7468ae5b68b1f61","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 78b9589fda266c71f0f9d0c858d4fa7381a890a5","Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 43f8f7946814c8e5f464518246fdbc69b6e32326","Linux 5.3"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:56:51.877996Z"},"published":"2026-08-15","updated":"2026-11-06","sourceUpdated":"2026-11-06T17:05:45.306Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74395","references":[{"url":"https://git.kernel.org/stable/c/6e15b770461eeaa0ff73934922cb670a6a9db04e"},{"url":"https://git.kernel.org/stable/c/9be9aca28424228586fe9211c373ebdb826ebb6c"},{"url":"https://git.kernel.org/stable/c/f345e744b6b087188cde2377da5cbe9713b61353"},{"url":"https://git.kernel.org/stable/c/1025dc2f7ba29b04b8687790fa91f9cd1a53141e"},{"url":"https://git.kernel.org/stable/c/7921821fc2b19c01588311f6e7468ae5b68b1f61"},{"url":"https://git.kernel.org/stable/c/5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989"},{"url":"https://git.kernel.org/stable/c/78b9589fda266c71f0f9d0c858d4fa7381a890a5"},{"url":"https://git.kernel.org/stable/c/43f8f7946814c8e5f464518246fdbc69b6e32326"}],"tags":["cve.org"],"epss":0.0022,"epssPercentile":0.12557,"ingestedAt":"2026-11-06T18:00:12.564Z","slug":"CVE-2026-74395","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/mlx5: Fix devx subscribe-event unwind NULL dereference\n\nMLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT() links event_sub into sub_list\nbefore initializing the fields used by the shared error path.\n\nIf eventfd_ctx_fdget() then fails, the unwind path dereferences\nevent_sub->ev_file in uverbs_uobject_put() and calls\nsubscribe_event_xa_dealloc() with an unset xa_key_level1.\n\nsubscribe_event_xa_alloc() creates the XA entry exactly once for a given\nkey_level1, on the first occurrence of that key. The unwind path must\ntherefore call subscribe_event_xa_dealloc() exactly once for it as well.\n\nEnforce that by adding devx_key_in_sub_list() and calling\nsubscribe_event_xa_dealloc() only when the last matching pending entry is\nbeing cleaned up.\n\n## Affected\n\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 6e15b770461eeaa0ff73934922cb670a6a9db04e`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 9be9aca28424228586fe9211c373ebdb826ebb6c`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < f345e744b6b087188cde2377da5cbe9713b61353`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 1025dc2f7ba29b04b8687790fa91f9cd1a53141e`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 7921821fc2b19c01588311f6e7468ae5b68b1f61`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 5100febf8e9d6c8c5ba8dc6534c6a5e3376e5989`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 78b9589fda266c71f0f9d0c858d4fa7381a890a5`\n- `Linux >= 7597385371425febdaa8c6a1da3625d4ffff16f5 < 43f8f7946814c8e5f464518246fdbc69b6e32326`\n- `Linux 5.3`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}