{"id":"CVE-2026-50095","kind":"vulnerability","aliases":["CVE-2026-50095"],"related":[],"title":"Esri ArcGIS Server: stored XSS lets unauthenticated attackers plant browser-executed script","description":"There is a stored cross site scripting issue in Esri ArcGIS Server 11.1 and earlier on Windows and Linux that in some configurations allows a remote unauthenticated attacker to store files that contain malicious code that may execute in the context of a victim’s browser. A patch is provided for ArcGIS Server software in General Availability and Extended support status, which includes versions 12.1, 12.0, 11.5, 11.3, and 11.1. Other versions are in mature or retired status, which are not patch eligible. Users working with unlisted versions are advised to upgrade and apply the patch.","summary":"Esri ArcGIS Server 11.1 and earlier on Windows and Linux has a stored cross-site scripting flaw in some configurations. A remote unauthenticated attacker can store files containing malicious code that runs in a victim's browser.","severity":"medium","cvss":6.1,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["arcgis-server","esri","infrastructure","linux","self-hosted","windows"],"not_affected_if":["unknown"],"how_to_check":"- Check the installed ArcGIS Server version against the patched list in the advisory (unknown exact build numbers in sources)\n- Confirm the host runs ArcGIS Server on Windows or Linux with the affected configuration (unknown which configuration the sources mean)","fix":"- Apply the Esri ArcGIS Server patch for supported releases 12.1, 12.0, 11.5, 11.3 or 11.1 (exact patch identifiers unknown)\n- Upgrade versions outside those lines to a supported release, then apply the patch","status":"open","published_at":"2026-10-26T18:17:48+00:00","first_seen_at":"2026-10-26T18:31:44+00:00","triaged_at":"2026-10-26T18:34:11+00:00","updated_at":"2026-10-26T18:34:11+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-10-26T18:34:11Z","model":"claude-haiku-5-5","output":{"fix":"- Apply the Esri ArcGIS Server patch for supported releases 12.1, 12.0, 11.5, 11.3 or 11.1 (exact patch identifiers unknown)\n- Upgrade versions outside those lines to a supported release, then apply the patch","reach":"internet","title":"Esri ArcGIS Server: stored XSS lets unauthenticated attackers plant browser-executed script","impact":"medium","summary":"Esri ArcGIS Server 11.1 and earlier on Windows and Linux has a stored cross-site scripting flaw in some configurations. A remote unauthenticated attacker can store files containing malicious code that runs in a victim's browser.","category":"infrastructure","nicknames":[],"who_cares":["arcgis-server","esri","windows","linux","self-hosted"],"confidence":0.6,"needs_auth":"no","worst_case":"Malicious script runs in victims' browsers on the ArcGIS site","analyst_note":"Find the Esri advisory with exact patched build numbers and the affected configuration; NVD text alone does not say which setup is vulnerable.","how_to_check":"- Check the installed ArcGIS Server version against the patched list in the advisory (unknown exact build numbers in sources)\n- Confirm the host runs ArcGIS Server on Windows or Linux with the affected configuration (unknown which configuration the sources mean)","needs_analyst":true,"not_affected_if":["unknown"],"who_is_affected":"ArcGIS Server 11.1 and earlier on Windows or Linux, in the configurations the advisory describes, where users can reach stored content served to browsers. Sources do not name the exact configuration, so unknown whether a default install is exposed. Teams on managed or unaffected versions can skip it.","user_interaction":"yes","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000665,"input_tokens":3419,"output_tokens":646,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':15A,18A '-50095':16A,19A '11.1':33B,80C,137C '11.3':135C '11.5':134C '12.0':133C '12.1':132C 'advis':157C 'allow':91C 'appli':161C 'arcgi':2A,21B,31B,78C,119C 'arcgis-serv':20B 'attack':8A,54B,95C 'avail':124C 'browser':11A,67B,113C 'browser-execut':10A 'code':60B,102C 'configur':50B,90C 'contain':58B,100C 'context':108C 'cross':44B,72C 'cross-sit':43B 'cve':14A,17A 'earlier':35B,82C 'elig':150C 'esri':1A,23B,30B,77C 'execut':12A,105C 'extend':126C 'file':57B,98C 'flaw':47B 'general':123C 'host':28B 'includ':130C 'infrastructur':24B 'issu':75C 'let':6A 'linux':25B,39B,86C 'malici':59B,101C 'matur':142C 'may':104C 'patch':115C,149C,163C 'plant':9A 'provid':117C 'remot':52B,93C 'retir':144C 'run':62B 'script':13A,46B,74C 'self':27B 'self-host':26B 'server':3A,22B,32B,79C,120C 'site':45B,73C 'softwar':121C 'status':128C,145C 'store':4A,42B,56B,71C,97C 'support':127C 'unauthent':7A,53B,94C 'unlist':154C 'upgrad':159C 'user':151C 'version':131C,139C,155C 'victim':65B,111C 'window':29B,37B,84C 'work':152C 'xss':5A","nicknames":[],"mitigations":[],"who_affected":"ArcGIS Server 11.1 and earlier on Windows or Linux, in the configurations the advisory describes, where users can reach stored content served to browsers. Sources do not name the exact configuration, so unknown whether a default install is exposed. Teams on managed or unaffected versions can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-26T18:17:48+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","cvss_by":"psirt@esri.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-50095","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50095","severity":null,"published_at":"2026-10-26T18:17:48+00:00","modified_at":"2026-10-26T18:31:27+00:00","first_seen_at":"2026-10-26T18:31:44+00:00","fetched_at":"2026-10-26T18:31:44+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}