{"id":"CVE-2026-118710","kind":"vulnerability","aliases":["CVE-2026-118710"],"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 on a victim's machine over a network. The sources do not say how a user is tricked into triggering it.","severity":"high","cvss":8.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["excel","microsoft-office","package","windows"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-11-10T19:19:46+00:00","first_seen_at":"2026-11-10T19:24:53+00:00","triaged_at":"2026-11-10T19:28:29+00:00","updated_at":"2026-11-10T19:28:29+00:00","category":"package","confidence":0.4,"triage":{"at":"2026-11-10T19:28:29Z","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 on a victim's machine over a network. The sources do not say how a user is tricked into triggering it.","audience":"everyone","category":"package","nicknames":[],"who_cares":["microsoft-office","excel","windows"],"confidence":0.4,"fix_status":"unknown","needs_auth":"no","worst_case":"Attacker runs code on the victim's computer over the network","analyst_note":"Check the Microsoft Security Response Center entry for CVE-2026-118710 for affected versions, the patch, and whether user interaction is required.","how_to_check":"- unknown","plain_action":"Update Microsoft Excel through Microsoft Update as soon as a fix from Microsoft is available.","product_name":"","needs_analyst":true,"not_affected_if":[],"who_is_affected":"Anyone running an affected version of Microsoft Office Excel. The sources do not name the affected versions or whether opening a file is enough to trigger the flaw.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000666,"input_tokens":4482,"output_tokens":436,"severity_before":"high"},"analyst_status":"queued","analyst_note":"Check the Microsoft Security Response Center entry for CVE-2026-118710 for affected versions, the patch, and whether user interaction is required.","search":"'-118710':15A,18A '-2026':14A,17A 'allow':68C 'attack':10A,38B,71C 'bug':30B 'code':12A,40B,74C 'cve':13A,16A 'excel':2A,19B,34B,67C 'execut':73C 'free':6A,29B,63C 'let':7A,35B 'machin':45B 'microsoft':1A,21B,32B,65C 'microsoft-offic':20B 'network':9A,48B,77C 'offic':22B,33B,66C 'packag':23B 'run':11A,39B 'say':53B 'sourc':50B 'trick':58B 'trigger':60B 'unauthor':37B,70C 'use':4A,27B,61C 'use-after-fre':3A,26B 'user':56B 'victim':43B 'window':24B","nicknames":[],"mitigations":[],"who_affected":"Anyone running an affected version of Microsoft Office Excel. The sources do not name the affected versions or whether opening a file is enough to trigger the flaw.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"everyone","plain_action":"Update Microsoft Excel through Microsoft Update as soon as a fix from Microsoft is available.","pkeys":[],"ptokens":[],"labels":["excel","high","microsoftoffice","package","windows"],"campaign_type":null,"search_a":"'-118710':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":"'attack':38B 'bug':30B 'code':40B 'excel':19B,34B 'free':29B 'let':35B 'machin':45B 'microsoft':21B,32B 'microsoft-offic':20B 'network':48B 'offic':22B,33B 'packag':23B 'run':39B 'say':53B 'sourc':50B 'trick':58B 'trigger':60B 'unauthor':37B 'use':27B 'use-after-fre':26B 'user':56B 'victim':43B 'window':24B","search_c":"'allow':68C 'attack':71C 'code':74C 'excel':67C 'execut':73C 'free':63C 'microsoft':65C 'network':77C 'offic':66C 'unauthor':70C 'use':61C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:19:46+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-2026-118710","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118710","severity":null,"published_at":"2026-11-10T19:19:46+00:00","modified_at":"2026-11-10T19:19:46+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"}