{"id":"CVE-2026-99235","published":"2026-11-02T16:17:48.790","lastModified":"2026-11-02T16:17:48.790","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Save the event file instead of the compatible histogram\n\ncreate_field_var_hist() creates a histogram on the matched event to\nsupply a field variable, and records it on the target so it can be torn\ndown later:\n\n\thist_data = find_compatible_hist(target_hist_data, file);\n\t...\n\t/* Save the compatible histogram information */\n\tvar_hist->hist_data = hist_data;\n\nhist_data is not the histogram it creates. It is one that was already\nthere, whose keys the new one copies. The saved pointer has a single\nuser, unregister_field_var_hists(), which runs when the target is\nremoved:\n\n\tfile = hist_data->field_var_hists[i]->hist_data->event_file;\n\nfind_compatible_hist() matches on keys alone, so it can pick one with no\nvariables of its own. check_var_refs() then returns false and the user\ncan remove it while the target still points at it:\n\n BUG: KASAN: slab-use-after-free in event_hist_trigger_free+0x2b2/0x320\n Read of size 8 at addr ffff8880093b90e0 by task init/1\n\n Freed by task 1:\n  kfree+0x154/0x420\n  event_hist_trigger_free+0x1d5/0x320\n  event_hist_trigger_parse+0x35f3/0x69e0\n  trigger_process_regex+0x1a6/0x250\n\nSave the event file instead. It is all the dereference ever wanted, and\nit does not go away when the user removes a trigger.","cvssScore":7.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/173914501b97236d7ea7dc2af7f30feddd4e1436","tags":[]},{"url":"https://git.kernel.org/stable/c/3609ada3c12cecfb0ae5ee82ef4f86c5f18a2dea","tags":[]},{"url":"https://git.kernel.org/stable/c/7a111ba0d1b74c99bc8f096565dc71945f694254","tags":[]},{"url":"https://git.kernel.org/stable/c/7cafc82e6153f05a221be678cd649d02e06ba909","tags":[]},{"url":"https://git.kernel.org/stable/c/8b307d64a60548e4a74cb746f74d7ed4bd49965e","tags":[]},{"url":"https://git.kernel.org/stable/c/9631dbccd3c649b567a5aafffea6b00634183997","tags":[]},{"url":"https://git.kernel.org/stable/c/a6165126b1a1b26342b55be6eb6ee23af8756aba","tags":[]},{"url":"https://git.kernel.org/stable/c/ac815a379644b2ad5008a009a3516ada31b5dd82","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}