{"id":"CVE-2026-109456","kind":"vulnerability","aliases":["CVE-2026-109456"],"related":[],"title":"Microsoft SharePoint: cross-site scripting lets an authorized user spoof pages","description":"Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.","summary":"Microsoft Office SharePoint does not properly neutralize input when generating web pages, which is a cross-site scripting flaw. An attacker with an account on the network can use it to spoof content shown to other users.","severity":"medium","cvss":4.6,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"Microsoft Office SharePoint","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["on-premises","other","sharepoint","windows-server"],"not_affected_if":["sharepoint-online-only"],"how_to_check":"- Check whether your organization runs on-premises Microsoft Office SharePoint Server (not SharePoint Online only).\n- Confirm the installed build against Microsoft's security update guide for CVE-2026-109456 (unknown from these sources).","fix":null,"status":"open","published_at":"2026-11-10T19:18:14+00:00","first_seen_at":"2026-11-10T19:24:23+00:00","triaged_at":"2026-11-10T20:04:25+00:00","updated_at":"2026-11-10T20:04:25+00:00","category":"other","confidence":0.5,"triage":{"at":"2026-11-10T20:04:25Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"network","title":"Microsoft SharePoint: cross-site scripting lets an authorized user spoof pages","impact":"low","summary":"Microsoft Office SharePoint does not properly neutralize input when generating web pages, which is a cross-site scripting flaw. An attacker with an account on the network can use it to spoof content shown to other users.","audience":"businesses","category":"other","nicknames":[],"who_cares":["sharepoint","windows-server","on-premises"],"confidence":0.5,"fix_status":"unknown","needs_auth":"yes","worst_case":"attacker spoofs page content shown to other users","analyst_note":"Find affected build ranges and the fixed build for CVE-2026-109456 in Microsoft's security update guide, and confirm the spoofing impact.","how_to_check":"- Check whether your organization runs on-premises Microsoft Office SharePoint Server (not SharePoint Online only).\n- Confirm the installed build against Microsoft's security update guide for CVE-2026-109456 (unknown from these sources).","plain_action":"","product_name":"Microsoft Office SharePoint","needs_analyst":true,"not_affected_if":["sharepoint-online-only"],"who_is_affected":"The flaw is in on-premises Microsoft Office SharePoint. Exposure requires an authorized account on the network. The sources do not name affected versions, so teams should check their installed SharePoint build against Microsoft's advisory.","user_interaction":"unknown","product_ecosystem":"vendor","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.00073,"input_tokens":4511,"output_tokens":558,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-109456':15A,18A '-2026':14A,17A 'account':54B 'allow':84C 'attack':51B,87C 'author':9A,86C 'content':63B 'cross':4A,46B,77C 'cross-sit':3A,45B,76C 'cve':13A,16A 'flaw':49B 'generat':39B,75C 'improp':68C 'input':37B,71C 'let':7A 'microsoft':1A,19A,30B,81C 'network':57B,93C 'neutral':36B,69C 'offic':31B,82C 'office':20A 'on-premis':22B 'page':12A,41B,74C 'perform':89C 'premis':24B 'proper':35B 'script':6A,48B,79C 'server':29B 'sharepoint':2A,21A,26B,32B,83C 'shown':64B 'site':5A,47B,78C 'spoof':11A,62B,90C 'use':59B 'user':10A,67B 'web':40B,73C 'window':28B 'windows-serv':27B","nicknames":[],"mitigations":[],"who_affected":"The flaw is in on-premises Microsoft Office SharePoint. Exposure requires an authorized account on the network. The sources do not name affected versions, so teams should check their installed SharePoint build against Microsoft's advisory.","tier":"C","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":["microsoftofficesharepoint","officesharepoint"],"ptokens":["microsoft","office","sharepoint"],"labels":["medium","onpremises","other","sharepoint","vendor","windowsserver"],"campaign_type":null,"search_a":"'-109456':15A,18A '-2026':14A,17A 'author':9A 'cross':4A 'cross-sit':3A 'cve':13A,16A 'let':7A 'microsoft':1A,19A 'office':20A 'page':12A 'script':6A 'sharepoint':2A,21A 'site':5A 'spoof':11A 'user':10A","search_b":"'account':54B 'attack':51B 'content':63B 'cross':46B 'cross-sit':45B 'flaw':49B 'generat':39B 'input':37B 'microsoft':30B 'network':57B 'neutral':36B 'offic':31B 'on-premis':22B 'page':41B 'premis':24B 'proper':35B 'script':48B 'server':29B 'sharepoint':26B,32B 'shown':64B 'site':47B 'spoof':62B 'use':59B 'user':67B 'web':40B 'window':28B 'windows-serv':27B","search_c":"'allow':84C 'attack':87C 'author':86C 'cross':77C 'cross-sit':76C 'generat':75C 'improp':68C 'input':71C 'microsoft':81C 'network':93C 'neutral':69C 'offic':82C 'page':74C 'perform':89C 'script':79C 'sharepoint':83C 'site':78C 'spoof':90C 'web':73C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:18:14+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-109456","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-109456","severity":null,"published_at":"2026-11-10T19:18:14+00:00","modified_at":"2026-11-10T19:18:14+00:00","first_seen_at":"2026-11-10T19:24:23+00:00","fetched_at":"2026-11-10T19:24:23+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"}