{"id":"CVE-2021-21193","published":"2021-03-16T15:15:13Z","modified":"2026-06-17T03:35:00Z","title":"Google Chromium Blink Use-After-Free Vulnerability","vendor":"Google","product":"Chromium Blink","tier":"core","eol":null,"description":{"text":"Use after free in Blink in Google Chrome prior to 89.0.4389.90 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.","provenance":"source","from":"NVD"},"summary":{"text":"A use-after-free flaw in the Blink rendering engine of Google Chromium (Chrome versions prior to 89.0.4389.90) can lead to heap corruption. A remote attacker can exploit it by getting a victim to open a crafted HTML page, which requires user interaction but no authentication or special configuration.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:13:02Z"},"cvss":{"score":8.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.0995,"percentile":0.95595,"date":"2026-10-31","provenance":"source"},"kev":{"dateAdded":"2021-11-03","dueDate":"2021-11-17","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-21193","provenance":"source"},"vulncheckKev":{"dateAdded":"2021-03-09","exploitedFirstSeen":"2021-03-09","ransomware":false,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2021-03-09"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2021-11-03"}],"evidenceTotal":2,"provenance":"source"},"exploited":true,"otx":null,"cwes":[{"id":"CWE-416","name":"Use After Free"}],"references":[{"url":"https://chromereleases.googleblog.com/2021/03/stable-channel-update-for-desktop_12.html","tags":["Release Notes"]},{"url":"https://crbug.com/1186287","tags":["Permissions Required"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N52OWF4BAP3JNK2QYGU3Q6QUVDZDCIMQ/","tags":["Release Notes"]},{"url":"https://security.gentoo.org/glsa/202104-08","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4886","tags":["Mailing List","Third Party Advisory"]},{"url":"https://chromereleases.googleblog.com/2021/03/stable-channel-update-for-desktop_12.html","tags":["Release Notes"]},{"url":"https://crbug.com/1186287","tags":["Permissions Required"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N52OWF4BAP3JNK2QYGU3Q6QUVDZDCIMQ/","tags":["Release Notes"]},{"url":"https://security.gentoo.org/glsa/202104-08","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4886","tags":["Mailing List","Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21193","tags":["US Government Resource"]}],"techniques":[{"id":"T1189","name":"Drive-by Compromise","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Malicious web page triggers browser exploitation","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page","start":63,"end":151}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1059","name":"Command and Scripting Interpreter","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Heap corruption enables attacker code execution","mappingType":"primary_impact","evidence":[{"from":"description","quote":"Use after free in Blink in Google Chrome","start":0,"end":40}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2021-8584","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-8584","exploited":true,"exploitedSince":"2021-11-03","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":1,"skipped":0,"earliest":"2022-03-28","earliestUrl":"https://github.com/mehrzad1994/CVE-2021-21193","repos":[{"name":"mehrzad1994/CVE-2021-21193","url":"https://github.com/mehrzad1994/CVE-2021-21193","stars":0,"created":"2022-03-28"}]},"first":{"date":"2022-03-28","source":"PoC-in-GitHub","url":"https://github.com/mehrzad1994/CVE-2021-21193"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1189"],"provenance":"ai"},{"stage":"primary","techniques":["T1059"],"provenance":"ai"}],"timeline":[{"date":"2021-03-09","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","provenance":"source"},{"date":"2021-03-16","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21193","provenance":"source"},{"date":"2021-11-03","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2021-11-03","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-8584","provenance":"source"},{"date":"2022-03-28","kind":"exploit-public","label":"First public exploit: PoC-in-GitHub","url":"https://github.com/mehrzad1994/CVE-2021-21193","provenance":"source"}],"speed":{"daysToPublicExploit":377,"firstExploitFrom":"PoC-in-GitHub","daysToKev":232},"priority":{"score":65.3,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 2063 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.12,"detail":"percentile 0.9559"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"1 PoC-in-GitHub repo"},{"name":"Mentioned in OTX pulses","points":0.0,"detail":"0 pulses"},{"name":"CVSS severity","points":6.16,"detail":"base score 8.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-class-google-chrome-cwe-416"}}