{"id":"AZL-112571","summary":"CVE-2026-99235 affecting package kernel 6.6.159.1-1","details":"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-\u003ehist_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-\u003efield_var_hists[i]-\u003ehist_data-\u003eevent_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.","modified":"2026-11-03T14:18:15.678786350Z","published":"2026-11-02T16:17:48Z","upstream":["CVE-2026-99235"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-99235"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.159.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-112571.json"}}],"schema_version":"1.9.2"}