{"id":"CVE-2026-66333","kind":"vulnerability","aliases":["CVE-2026-66333"],"related":[],"title":"AMI Aptio BIOS: out-of-bounds read lets privileged local users crash firmware update","description":"AMI APTIOV contains vulnerabilities in BIOS where\nprivileged users may cause the “Out-of-Bounds Read” by\nlocal access. Successful exploitation of this vulnerability may lead to a\ndenial of service during firmware update processing, such as a crash or failed\nupdate if the out-of-bounds read hits unmapped memory. It could also impact\nConfidentiality, and Availability.","summary":"AMI Aptio BIOS firmware contains an out-of-bounds read that a privileged local user can trigger. Successful exploitation may crash the firmware update process or cause a failed update, and could also expose or disrupt data.","severity":"medium","cvss":4.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["ami","aptio","bios","firmware","infrastructure"],"not_affected_if":["no-local-privileged-access"],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-10T17:17:46+00:00","first_seen_at":"2026-11-10T17:22:44+00:00","triaged_at":"2026-11-10T17:24:41+00:00","updated_at":"2026-11-10T17:24:41+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-11-10T17:24:41Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"AMI Aptio BIOS: out-of-bounds read lets privileged local users crash firmware update","impact":"medium","summary":"AMI Aptio BIOS firmware contains an out-of-bounds read that a privileged local user can trigger. Successful exploitation may crash the firmware update process or cause a failed update, and could also expose or disrupt data.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["bios","firmware","aptio","ami"],"confidence":0.6,"fix_status":"unknown","needs_auth":"yes","worst_case":"firmware update crashes or fails; some data exposure locally","analyst_note":"Find the AMI security bulletin for CVE-2026-66333 to get affected Aptio versions and the firmware fix; NVD page at https://nvd.nist.gov/vuln/detail/CVE-2026-66333 gives no versions.","how_to_check":"- unknown","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["no-local-privileged-access"],"who_is_affected":"Systems running AMI Aptio BIOS firmware, typically server and workstation motherboards. Exploitation requires privileged local access to the machine. The sources do not name affected firmware versions or board vendors.","user_interaction":"no","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000704,"input_tokens":4592,"output_tokens":489,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':17A,20A '-66333':18A,21A 'access':84C 'also':60B,120C 'ami':1A,22B,27B,65C 'aptio':2A,23B,28B 'aptiov':66C 'avail':124C 'bio':3A,24B,29B,70C 'bound':7A,36B,80C,113C 'caus':54B,75C 'confidenti':122C 'contain':31B,67C 'could':59B,119C 'crash':13A,48B,104C 'cve':16A,19A 'data':64B 'denial':94C 'disrupt':63B 'exploit':46B,86C 'expos':61B 'fail':56B,106C 'firmwar':14A,25B,30B,50B,98C 'hit':115C 'impact':121C 'infrastructur':26B 'lead':91C 'let':9A 'local':11A,41B,83C 'may':47B,74C,90C 'memori':117C 'out-of-bound':4A,33B,77C,110C 'privileg':10A,40B,72C 'process':52B,100C 'read':8A,37B,81C,114C 'servic':96C 'success':45B,85C 'trigger':44B 'unmap':116C 'updat':15A,51B,57B,99C,107C 'user':12A,42B,73C 'vulner':68C,89C","nicknames":[],"mitigations":[],"who_affected":"Systems running AMI Aptio BIOS firmware, typically server and workstation motherboards. Exploitation requires privileged local access to the machine. The sources do not name affected firmware versions or board vendors.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["ami","aptio","bios","firmware","infrastructure","medium"],"campaign_type":null,"search_a":"'-2026':17A,20A '-66333':18A,21A 'ami':1A 'aptio':2A 'bio':3A 'bound':7A 'crash':13A 'cve':16A,19A 'firmwar':14A 'let':9A 'local':11A 'out-of-bound':4A 'privileg':10A 'read':8A 'updat':15A 'user':12A","search_b":"'also':60B 'ami':22B,27B 'aptio':23B,28B 'bio':24B,29B 'bound':36B 'caus':54B 'contain':31B 'could':59B 'crash':48B 'data':64B 'disrupt':63B 'exploit':46B 'expos':61B 'fail':56B 'firmwar':25B,30B,50B 'infrastructur':26B 'local':41B 'may':47B 'out-of-bound':33B 'privileg':40B 'process':52B 'read':37B 'success':45B 'trigger':44B 'updat':51B,57B 'user':42B","search_c":"'access':84C 'also':120C 'ami':65C 'aptiov':66C 'avail':124C 'bio':70C 'bound':80C,113C 'caus':75C 'confidenti':122C 'contain':67C 'could':119C 'crash':104C 'denial':94C 'exploit':86C 'fail':106C 'firmwar':98C 'hit':115C 'impact':121C 'lead':91C 'local':83C 'may':74C,90C 'memori':117C 'out-of-bound':77C,110C 'privileg':72C 'process':100C 'read':81C,114C 'servic':96C 'success':85C 'unmap':116C 'updat':99C,107C 'user':73C 'vulner':68C,89C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T17:17:46+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"biossecurity@ami.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-66333","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66333","severity":null,"published_at":"2026-11-10T17:17:46+00:00","modified_at":"2026-11-10T17:17:46+00:00","first_seen_at":"2026-11-10T17:22:44+00:00","fetched_at":"2026-11-10T17:22:44+00:00","note":null}],"documents":[],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}