{"id":"CVE-2021-30632","kind":"vulnerability","aliases":["CVE-2021-30632"],"related":[],"title":"Google Chromium V8: Google Chromium V8 Out-of-Bounds Write Vulnerability","description":"Google Chromium V8 Engine contains an out-of-bounds write vulnerability that allows a remote attacker to potentially exploit heap corruption 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 bug in the Chromium V8 JavaScript engine lets a crafted web page write outside a memory buffer and corrupt the heap. An attacker who gets a victim to load the page can potentially run code in the browser.","severity":"high","cvss":8.8,"epss":0.6319,"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":["patched-browser"],"how_to_check":"Open the browser's version page (chrome://version in Chrome or Edge, opera://about in Opera) and compare against the fixed version in the vendor advisory.","fix":"Update Chrome, Edge, Opera or other Chromium-based browsers to the vendor's patched build.","status":"open","published_at":"2021-10-08T21:15:07+00:00","first_seen_at":"2026-10-23T19:11:53+00:00","triaged_at":"2026-10-23T21:39:38+00:00","updated_at":"2026-10-23T21:57:35+00:00","category":"runtime","confidence":0.7,"triage":{"at":"2026-10-23T21:39:38Z","model":"claude-haiku-5-5","output":{"fix":"Update Chrome, Edge, Opera or other Chromium-based browsers to the vendor's patched build.\nunknown","reach":"internet","impact":"high","summary":"A bug in the Chromium V8 JavaScript engine lets a crafted web page write outside a memory buffer and corrupt the heap. An attacker who gets a victim to load the page can potentially run code in the browser.","category":"runtime","who_cares":["chrome","edge","opera","chromium","browsers"],"confidence":0.7,"needs_auth":"no","worst_case":"Attacker runs code in the browser after the victim visits a crafted page.","analyst_note":"Find the fixed Chrome version and the Chrome Releases advisory for CVE-2021-30632 (KEV lists it as exploited; fixed versions were not in the sources).","how_to_check":"Open the browser's version page (chrome://version in Chrome or Edge, opera://about in Opera) and compare against the fixed version in the vendor advisory.\nunknown","needs_analyst":true,"not_affected_if":["patched-browser"],"user_interaction":"yes","needs_special_setup":"no","severity_if_unknown":"high"},"cost_usd":0.000494,"input_tokens":2896,"output_tokens":408,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2021':14A,17A '-30632':15A,18A 'action':118C 'affect':98C 'allow':81C 'appli':119C 'attack':52B,84C 'bound':10A,77C 'browser':22B,67B,101C 'buffer':46B 'bug':30B 'chrome':23B,111C 'chromium':2A,5A,20A,24B,33B,69C,104C 'cisa':116C 'code':64B 'contain':72C 'corrupt':48B,89C 'could':97C 'craft':39B,92C 'cve':13A,16A 'edg':25B,113C 'engin':36B,71C 'exploit':26B,87C 'get':54B 'googl':1A,4A,68C,110C 'google':19A 'heap':50B,88C 'html':93C 'includ':105C 'instruct':123C 'javascript':35B 'let':37B 'limit':108C 'load':58B 'memori':45B 'microsoft':112C 'multipl':99C 'opera':27B,115C 'out-of-bound':7A,74C 'outsid':43B 'page':41B,60B,94C 'per':121C 'potenti':62B,86C 'remot':83C 'requir':117C 'run':63B 'runtim':28B 'updat':120C 'util':103C 'v8':3A,6A,21A,34B,70C 'vendor':122C 'via':90C 'victim':56B 'vulner':12A,79C,96C 'web':40B,100C 'write':11A,42B,78C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2021-10-08T21:15:07+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-2021-30632","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-30632","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":"2026-10-25T12:39:25+00:00","note":null},{"source":"epss","external_id":"CVE-2021-30632","url":"https://api.first.org/data/v1/epss?cve=CVE-2021-30632","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-2021-30632","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-30632","severity":null,"published_at":"2021-10-08T21:15:07+00:00","modified_at":"2026-06-17T03:50:35+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"}