{"id":"CVE-2026-121166","kind":"vulnerability","aliases":["CVE-2026-121166"],"related":[],"title":"Chrome: PDFium type confusion lets a crafted PDF run code","description":"Type confusion in PDFium in Google Chrome prior to 157.0.8103.38 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted PDF file. (Chromium security severity: High)","summary":"A type confusion bug in PDFium, the PDF engine inside Google Chrome, lets a crafted PDF file execute arbitrary code inside the browser sandbox. Chromium rates it High severity, and the sources do not say whether it is exploited in the wild.","severity":"high","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["chrome","endpoints","linux","macos","runtime","windows"],"not_affected_if":["chrome-updated","pdf-viewing-disabled"],"how_to_check":"- Check the Chrome version under Chrome menu > Help > About Google Chrome, or run `chrome --version` on a managed machine.\n- Confirm the installed version is `157.0.8103.38` or later.","fix":"- Google Chrome: move to `157.0.8103.38` or later.","status":"open","published_at":"2026-11-03T21:17:24+00:00","first_seen_at":"2026-11-03T21:19:23+00:00","triaged_at":"2026-11-03T21:23:23+00:00","updated_at":"2026-11-03T21:23:23+00:00","category":"runtime","confidence":0.7,"triage":{"at":"2026-11-03T21:23:23Z","model":"claude-haiku-5-5","output":{"fix":"- Google Chrome: move to `157.0.8103.38` or later.","reach":"internet","title":"Chrome: PDFium type confusion lets a crafted PDF run code","impact":"high","summary":"A type confusion bug in PDFium, the PDF engine inside Google Chrome, lets a crafted PDF file execute arbitrary code inside the browser sandbox. Chromium rates it High severity, and the sources do not say whether it is exploited in the wild.","audience":"everyone","category":"runtime","nicknames":[],"who_cares":["chrome","windows","macos","linux","endpoints"],"confidence":0.7,"fix_status":"available","needs_auth":"no","worst_case":"Attacker runs code inside the Chrome sandbox on the user's machine","analyst_note":"","how_to_check":"- Check the Chrome version under Chrome menu > Help > About Google Chrome, or run `chrome --version` on a managed machine.\n- Confirm the installed version is `157.0.8103.38` or later.","plain_action":"Update Google Chrome to version 157.0.8103.38 or later: Chrome menu > Help > About Google Chrome.","needs_analyst":false,"not_affected_if":["chrome-updated","pdf-viewing-disabled"],"who_is_affected":"Any device running Google Chrome before 157.0.8103.38 is exposed when it opens a crafted PDF, including PDFs opened inline from a web page. Managed fleets should check the Chrome version on every endpoint. Systems that do not run Chrome, or that run a patched build, can skip it.","user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000701,"input_tokens":4105,"output_tokens":581,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-121166':13A,16A '-2026':12A,15A '157.0.8103.38':74C 'allow':75C 'arbitrari':41B,81C 'attack':78C 'browser':45B 'bug':26B 'chrome':1A,17B,34B,71C 'chromium':47B,91C 'code':10A,42B,82C 'confus':4A,25B,66C 'craft':7A,37B,88C 'cve':11A,14A 'endpoint':18B 'engin':31B 'execut':40B,80C 'exploit':61B 'file':39B,90C 'googl':33B,70C 'high':50B,94C 'insid':32B,43B,83C 'let':5A,35B 'linux':19B 'maco':20B 'pdf':8A,30B,38B,89C 'pdfium':2A,28B,68C 'prior':72C 'rate':48B 'remot':77C 'run':9A 'runtim':21B 'sandbox':46B,85C 'say':57B 'secur':92C 'sever':51B,93C 'sourc':54B 'type':3A,24B,65C 'via':86C 'whether':58B 'wild':64B 'window':22B","nicknames":[],"mitigations":[],"who_affected":"Any device running Google Chrome before 157.0.8103.38 is exposed when it opens a crafted PDF, including PDFs opened inline from a web page. Managed fleets should check the Chrome version on every endpoint. Systems that do not run Chrome, or that run a patched build, can skip it.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"available","audience":"everyone","plain_action":"Update Google Chrome to version 157.0.8103.38 or later: Chrome menu > Help > About Google Chrome.","pkeys":[],"ptokens":[],"labels":["chrome","endpoints","high","linux","macos","runtime","windows"],"campaign_type":null,"first_public_at":"2026-11-03T21:17:24+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-121166","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121166","severity":null,"published_at":"2026-11-03T21:17:24+00:00","modified_at":"2026-11-03T21:17:24+00:00","first_seen_at":"2026-11-03T21:19:23+00:00","fetched_at":"2026-11-03T21:19:23+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"}