{"id":"CVE-2021-21224","kind":"vulnerability","aliases":["CVE-2021-21224"],"related":[],"title":"Google Chromium V8: Google Chromium V8 Type Confusion Vulnerability","description":"Google Chromium V8 Engine contains a type confusion vulnerability that allows a remote attacker to execute code inside a sandbox via a crafted HTML page. This vulnerability could affect multiple web browsers that utilize Chromium, including, but not limited to, Google Chrome, Microsoft Edge, and Opera.\n\nCISA required action: Apply updates per vendor instructions.","summary":"A type confusion bug in the Chromium V8 JavaScript engine lets a remote attacker run code inside the browser sandbox by serving a crafted HTML page. It is listed as actively exploited in the wild.","severity":"high","cvss":8.8,"epss":0.84173,"exploited":true,"exploited_at":"2021-11-03T00:00:00+00:00","products":[{"name":"Google Chromium V8","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["browsers","chrome","chromium","edge","exploited","opera","runtime"],"not_affected_if":["fully-patched-browser"],"how_to_check":"Open chrome://version (or edge://version, opera://about) and compare the version to the vendor fixed release.","fix":"Update Chrome, Edge, Opera or any other Chromium-based browser to a release that includes the vendor fix, as CISA requires.","status":"open","published_at":"2021-04-26T17:15:08+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:39:46+00:00","updated_at":"2026-10-23T21:57:35+00:00","category":"runtime","confidence":0.8,"triage":{"at":"2026-10-23T21:39:46Z","model":"claude-haiku-5-5","output":{"fix":"Update Chrome, Edge, Opera or any other Chromium-based browser to a release that includes the vendor fix, as CISA requires.\nunknown","reach":"internet","impact":"high","summary":"A type confusion bug in the Chromium V8 JavaScript engine lets a remote attacker run code inside the browser sandbox by serving a crafted HTML page. It is listed as actively exploited in the wild.","category":"runtime","who_cares":["chrome","edge","chromium","opera","browsers"],"confidence":0.8,"needs_auth":"no","worst_case":"Attacker runs code inside the browser sandbox after the victim visits a page","analyst_note":"Find the fixed Chromium version and advisory from the Chrome Releases blog or the NVD entry for CVE-2021-21224 so how_to_check and fix can be filled with concrete versions.","how_to_check":"Open chrome://version (or edge://version, opera://about) and compare the version to the vendor fixed release.\nunknown","needs_analyst":true,"not_affected_if":["fully-patched-browser"],"user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000493,"input_tokens":2886,"output_tokens":409,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2021':11A,14A '-21224':12A,15A 'action':109C 'activ':56B 'affect':89C 'allow':71C 'appli':110C 'attack':39B,74C 'browser':19B,44B,92C 'bug':29B 'chrome':20B,102C 'chromium':2A,5A,17A,21B,32B,62C,95C 'cisa':107C 'code':41B,77C 'confus':8A,28B,68C 'contain':65C 'could':88C 'craft':49B,83C 'cve':10A,13A 'edg':22B,104C 'engin':35B,64C 'execut':76C 'exploit':23B,57B 'googl':1A,4A,61C,101C 'google':16A 'html':50B,84C 'includ':96C 'insid':42B,78C 'instruct':114C 'javascript':34B 'let':36B 'limit':99C 'list':54B 'microsoft':103C 'multipl':90C 'opera':24B,106C 'page':51B,85C 'per':112C 'remot':38B,73C 'requir':108C 'run':40B 'runtim':25B 'sandbox':45B,80C 'serv':47B 'type':7A,27B,67C 'updat':111C 'util':94C 'v8':3A,6A,18A,33B,63C 'vendor':113C 'via':81C 'vulner':9A,69C,87C 'web':91C 'wild':60B","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2021-04-26T17:15:08+00:00","kev":{"dateAdded":"2021-11-03","dueDate":"2021-11-17","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvss_by":"nvd@nist.gov","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2021-21224","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-21224","severity":null,"published_at":"2021-11-03T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:53+00:00","fetched_at":"2026-10-25T20:35:38+00:00","note":null},{"source":"epss","external_id":"CVE-2021-21224","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-21224","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:44+00:00","fetched_at":"2026-10-23T19:13:44+00:00","note":null},{"source":"nvd","external_id":"CVE-2021-21224","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21224","severity":null,"published_at":"2021-04-26T17:15:08+00:00","modified_at":"2026-06-17T03:35:04+00:00","first_seen_at":"2026-10-23T21:57:35+00:00","fetched_at":"2026-10-23T21:57:35+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"}