CVE-2021-21220
Google Chromium V8 Improper Input Validation Vulnerability
- Published
- Apr 26, 2021
- Updated
- Oct 21, 2025
- Assigning CNA
- Chrome
- Evidence observed
- Nov 3, 2021
Primary CVSS
nvd · CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HHigh · next 30 days
- Percentile
- 99.4%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
CISA Known Exploited
This CVE appears in the CISA Known Exploited Vulnerabilities catalog.
Summary
Insufficient validation of untrusted input in V8 in Google Chrome prior to 89.0.4389.128 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.
Sources
5- CVE-2021-21220Research
Educational presentation detailing the exploitation of CVE-2021-21220, a V8 JIT type confusion leading to OOB access and RCE via WebAssembly, with mitigation analysis.
- CVE-2021-21220Exploit
Browser-based CVE-2021-21220 exploit delivering a reverse shell via shellcode and a C2 implant for remote command execution on Windows targets.
Proof-of-concept exploit for CVE-2021-21220, a Chrome V8 vulnerability, with references to technical analysis and exploitation details.
Responsible use
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