{"id":"CVE-2026-118716","kind":"vulnerability","aliases":["CVE-2026-118716"],"related":[],"title":"Microsoft Excel: use-after-free lets a network attacker run code","description":"Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.","summary":"A use-after-free bug in Microsoft Office Excel lets an unauthorized attacker run code over a network. NVD rates it high (CVSS 8.8).","severity":"high","cvss":8.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["excel","microsoft-office","vendor","windows"],"not_affected_if":[],"how_to_check":"- Open Excel and check the version under File > Account (or Excel > About Excel on Mac) against the fixed build in Microsoft's advisory, which the sources do not name.","fix":null,"status":"open","published_at":"2026-11-10T19:19:47+00:00","first_seen_at":"2026-11-10T19:24:53+00:00","triaged_at":"2026-11-10T19:28:23+00:00","updated_at":"2026-11-10T19:28:23+00:00","category":"vendor","confidence":0.5,"triage":{"at":"2026-11-10T19:28:23Z","model":"claude-haiku-5-5","output":{"fix":"- unknown","reach":"network","title":"Microsoft Excel: use-after-free lets a network attacker run code","impact":"high","summary":"A use-after-free bug in Microsoft Office Excel lets an unauthorized attacker run code over a network. NVD rates it high (CVSS 8.8).","audience":"businesses","category":"vendor","nicknames":[],"who_cares":["excel","microsoft-office","windows"],"confidence":0.5,"fix_status":"unknown","needs_auth":"no","worst_case":"Attacker runs arbitrary code on the affected machine over the network.","analyst_note":"Find Microsoft's security update guide entry for CVE-2026-118716 to confirm affected builds, fixed versions and whether user interaction (opening a file) is required.","how_to_check":"- Open Excel and check the version under File > Account (or Excel > About Excel on Mac) against the fixed build in Microsoft's advisory, which the sources do not name.\n- unknown","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":[],"who_is_affected":"Organizations running Microsoft Office Excel are potentially exposed, since the flaw is reachable over a network without an account. The sources do not say which Excel builds or file-handling paths are affected, so the exposed configuration is unknown.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000693,"input_tokens":4482,"output_tokens":490,"severity_before":"high"},"analyst_status":"queued","analyst_note":"Find Microsoft's security update guide entry for CVE-2026-118716 to confirm affected builds, fixed versions and whether user interaction (opening a file) is required.","search":"'-118716':15A,18A '-2026':14A,17A '8.8':49B 'allow':57C 'attack':10A,38B,60C 'bug':30B 'code':12A,40B,63C 'cve':13A,16A 'cvss':48B 'excel':2A,19B,34B,56C 'execut':62C 'free':6A,29B,52C 'high':47B 'let':7A,35B 'microsoft':1A,21B,32B,54C 'microsoft-offic':20B 'network':9A,43B,66C 'nvd':44B 'offic':22B,33B,55C 'rate':45B 'run':11A,39B 'unauthor':37B,59C 'use':4A,27B,50C 'use-after-fre':3A,26B 'vendor':23B 'window':24B","nicknames":[],"mitigations":[],"who_affected":"Organizations running Microsoft Office Excel are potentially exposed, since the flaw is reachable over a network without an account. The sources do not say which Excel builds or file-handling paths are affected, so the exposed configuration is unknown.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["excel","high","microsoftoffice","vendor","windows"],"campaign_type":null,"search_a":"'-118716':15A,18A '-2026':14A,17A 'attack':10A 'code':12A 'cve':13A,16A 'excel':2A 'free':6A 'let':7A 'microsoft':1A 'network':9A 'run':11A 'use':4A 'use-after-fre':3A","search_b":"'8.8':49B 'attack':38B 'bug':30B 'code':40B 'cvss':48B 'excel':19B,34B 'free':29B 'high':47B 'let':35B 'microsoft':21B,32B 'microsoft-offic':20B 'network':43B 'nvd':44B 'offic':22B,33B 'rate':45B 'run':39B 'unauthor':37B 'use':27B 'use-after-fre':26B 'vendor':23B 'window':24B","search_c":"'allow':57C 'attack':60C 'code':63C 'excel':56C 'execut':62C 'free':52C 'microsoft':54C 'network':66C 'offic':55C 'unauthor':59C 'use':50C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:19:47+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/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-2026-118716","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118716","severity":null,"published_at":"2026-11-10T19:19:47+00:00","modified_at":"2026-11-10T19:19:47+00:00","first_seen_at":"2026-11-10T19:24:53+00:00","fetched_at":"2026-11-10T19:24:53+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"}