{"id":"CVE-2026-118723","kind":"vulnerability","aliases":["CVE-2026-118723"],"related":[],"title":"Microsoft Excel: untrusted pointer use lets a local attacker run code","description":"Untrusted pointer dereference in Microsoft Office Excel allows an unauthorized attacker to execute code locally.","summary":"A flaw in Microsoft Office Excel lets an unauthorized attacker trigger an untrusted pointer dereference that can run code on the machine. The attack is local, so the attacker needs access to the computer or a way to get a user to open a crafted file.","severity":"high","cvss":7.8,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"Microsoft Office Excel","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["excel","microsoft-office","package","windows"],"not_affected_if":[],"how_to_check":"- Open Excel and check the version under File > Account > About Excel.\n- Confirm whether Microsoft Office updates are installed through Microsoft AutoUpdate or Windows Update.","fix":null,"status":"open","published_at":"2026-11-10T19:19:48+00:00","first_seen_at":"2026-11-10T19:24:54+00:00","triaged_at":"2026-11-10T19:40:36+00:00","updated_at":"2026-11-10T19:40:36+00:00","category":"package","confidence":0.5,"triage":{"at":"2026-11-10T19:40:36Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"Microsoft Excel: untrusted pointer use lets a local attacker run code","impact":"high","summary":"A flaw in Microsoft Office Excel lets an unauthorized attacker trigger an untrusted pointer dereference that can run code on the machine. The attack is local, so the attacker needs access to the computer or a way to get a user to open a crafted file.","audience":"businesses","category":"package","nicknames":[],"who_cares":["microsoft-office","excel","windows"],"confidence":0.5,"fix_status":"unknown","needs_auth":"unknown","worst_case":"Code runs on the local machine with the attacker's privileges.","analyst_note":"Find affected Excel versions, the Microsoft advisory fix, and whether a user must open a file, at https://nvd.nist.gov/vuln/detail/CVE-2026-118723.","how_to_check":"- Open Excel and check the version under File > Account > About Excel.\n- Confirm whether Microsoft Office updates are installed through Microsoft AutoUpdate or Windows Update.","plain_action":"","product_name":"Microsoft Office Excel","needs_analyst":true,"not_affected_if":[],"who_is_affected":"Organizations running Microsoft Office Excel on Windows or Mac. The sources do not name affected versions or confirm whether opening a crafted file is required, so unknown.","user_interaction":"unknown","product_ecosystem":"vendor","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000717,"input_tokens":4494,"output_tokens":535,"severity_before":"high"},"analyst_status":"queued","analyst_note":"Find affected Excel versions, the Microsoft advisory fix, and whether a user must open a file, at https://nvd.nist.gov/vuln/detail/CVE-2026-118723.","search":"'-118723':14A,17A '-2026':13A,16A 'access':57B 'allow':80C 'attack':9A,36B,50B,55B,83C 'code':11A,45B,86C 'comput':60B 'craft':71B 'cve':12A,15A 'derefer':41B,75C 'excel':2A,20A,21B,32B,79C 'execut':85C 'file':72B 'flaw':28B 'get':65B 'let':6A,33B 'local':8A,52B,87C 'machin':48B 'microsoft':1A,18A,23B,30B,77C 'microsoft-offic':22B 'need':56B 'offic':24B,31B,78C 'office':19A 'open':69B 'packag':25B 'pointer':4A,40B,74C 'run':10A,44B 'trigger':37B 'unauthor':35B,82C 'untrust':3A,39B,73C 'use':5A 'user':67B 'way':63B 'window':26B","nicknames":[],"mitigations":[],"who_affected":"Organizations running Microsoft Office Excel on Windows or Mac. The sources do not name affected versions or confirm whether opening a crafted file is required, so unknown.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":["microsoftofficeexcel","officeexcel"],"ptokens":["excel","microsoft","office"],"labels":["excel","high","microsoftoffice","package","vendor","windows"],"campaign_type":null,"search_a":"'-118723':14A,17A '-2026':13A,16A 'attack':9A 'code':11A 'cve':12A,15A 'excel':2A,20A 'let':6A 'local':8A 'microsoft':1A,18A 'office':19A 'pointer':4A 'run':10A 'untrust':3A 'use':5A","search_b":"'access':57B 'attack':36B,50B,55B 'code':45B 'comput':60B 'craft':71B 'derefer':41B 'excel':21B,32B 'file':72B 'flaw':28B 'get':65B 'let':33B 'local':52B 'machin':48B 'microsoft':23B,30B 'microsoft-offic':22B 'need':56B 'offic':24B,31B 'open':69B 'packag':25B 'pointer':40B 'run':44B 'trigger':37B 'unauthor':35B 'untrust':39B 'user':67B 'way':63B 'window':26B","search_c":"'allow':80C 'attack':83C 'code':86C 'derefer':75C 'excel':79C 'execut':85C 'local':87C 'microsoft':77C 'offic':78C 'pointer':74C 'unauthor':82C 'untrust':73C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:19:48+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-118723","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118723","severity":null,"published_at":"2026-11-10T19:19:48+00:00","modified_at":"2026-11-10T19:19:48+00:00","first_seen_at":"2026-11-10T19:24:54+00:00","fetched_at":"2026-11-10T19:24:54+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"}