{"id":"CVE-2026-118331","kind":"vulnerability","aliases":["CVE-2026-118331"],"related":[],"title":"Chrome: FileAPI input validation flaw lets crafted page run code","description":"Improper input validation in FileAPI in Google Chrome prior to 156.0.8078.73 allowed a remote attacker to potentially execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: Critical)","summary":"Google Chrome before 156.0.8078.73 mishandles input in its FileAPI, so a crafted HTML page can make the browser run attacker code inside the renderer sandbox. Chromium rates the flaw Critical.","severity":"critical","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["browsers","chrome","desktop-fleet","runtime"],"not_affected_if":["chrome-156.0.8078.73-or-later"],"how_to_check":"- Run `chrome://version` in Chrome and compare the version with `156.0.8078.73`\n- On managed fleets, check the installed Chrome build with the endpoint management tool\n- Chromium-based browsers (Edge, Brave) may need their own version check, which the sources do not say","fix":"- Update Google Chrome to `156.0.8078.73` or later\n- Restart the browser after the update so the new build is running\n- Update other Chromium-based browsers when their vendors ship the fix, which the sources do not say","status":"open","published_at":"2026-10-27T23:17:01+00:00","first_seen_at":"2026-10-27T23:29:43+00:00","triaged_at":"2026-10-27T23:31:52+00:00","updated_at":"2026-10-27T23:31:52+00:00","category":"runtime","confidence":0.7,"triage":{"at":"2026-10-27T23:31:52Z","model":"claude-haiku-5-5","output":{"fix":"- Update Google Chrome to `156.0.8078.73` or later\n- Restart the browser after the update so the new build is running\n- Update other Chromium-based browsers when their vendors ship the fix, which the sources do not say","reach":"internet","title":"Chrome: FileAPI input validation flaw lets crafted page run code","impact":"high","summary":"Google Chrome before 156.0.8078.73 mishandles input in its FileAPI, so a crafted HTML page can make the browser run attacker code inside the renderer sandbox. Chromium rates the flaw Critical.","category":"runtime","nicknames":[],"who_cares":["chrome","browsers","desktop-fleet"],"confidence":0.7,"needs_auth":"no","worst_case":"Attacker runs code inside the browser renderer sandbox via a web page","analyst_note":"Check the Chrome release notes and the Chromium security advisory for CVE-2026-118331 to confirm sandbox escape status and affected channels.","how_to_check":"- Run `chrome://version` in Chrome and compare the version with `156.0.8078.73`\n- On managed fleets, check the installed Chrome build with the endpoint management tool\n- Chromium-based browsers (Edge, Brave) may need their own version check, which the sources do not say","needs_analyst":true,"not_affected_if":["chrome-156.0.8078.73-or-later"],"who_is_affected":"Anyone running Google Chrome older than 156.0.8078.73 is exposed, since the attack needs only a victim who opens a crafted page. Teams that manage browsers on employee machines or kiosks should look at those, and web servers and apps do not need changes for this. Systems on a version at or above the fixed build can skip it.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"critical"},"cost_usd":0.000646,"input_tokens":3298,"output_tokens":632,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-118331':13A,16A '-2026':12A,15A '156.0.8078.73':26B,63C 'allow':64C 'arbitrari':71C 'attack':42B,67C 'browser':17B,40B 'chrome':1A,18B,24B,60C 'chromium':48B,81C 'code':10A,43B,72C 'craft':7A,34B,78C 'critic':52B,84C 'cve':11A,14A 'desktop':20B 'desktop-fleet':19B 'execut':70C 'fileapi':2A,31B,57C 'flaw':5A,51B 'fleet':21B 'googl':23B,59C 'html':35B,79C 'improp':53C 'input':3A,28B,54C 'insid':44B,73C 'let':6A 'make':38B 'mishandl':27B 'page':8A,36B,80C 'potenti':69C 'prior':61C 'rate':49B 'remot':66C 'render':46B 'run':9A,41B 'runtim':22B 'sandbox':47B,75C 'secur':82C 'sever':83C 'valid':4A,55C 'via':76C","nicknames":[],"mitigations":[],"who_affected":"Anyone running Google Chrome older than 156.0.8078.73 is exposed, since the attack needs only a victim who opens a crafted page. Teams that manage browsers on employee machines or kiosks should look at those, and web servers and apps do not need changes for this. Systems on a version at or above the fixed build can skip it.","tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T23:17:01+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-118331","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118331","severity":null,"published_at":"2026-10-27T23:17:01+00:00","modified_at":"2026-10-27T23:17:01+00:00","first_seen_at":"2026-10-27T23:29:43+00:00","fetched_at":"2026-10-27T23:29:43+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"}