CVE-2021-21220
Actively exploited. CVE-2021-21220 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.
Public exploit code is available. Proof-of-concept or working exploit code for CVE-2021-21220 is indexed in Metasploit and GitHub PoC. Expect opportunistic scanning and exploitation attempts — prioritize remediation.
Google Chromium V8 Engine contains an improper input validation 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.
CSIRTS triage
- What
- Google Chromium V8 Engine contains an improper input validation vulnerability that allows a remote attacker to potentially exploit heap corruption via a crafted HTML page.
- Who is affected
- Multiple web browsers utilizing Chromium, including Google Chrome, Microsoft Edge, and Opera, are affected.
- Urgency
- Remediation is critical due to active exploitation and the potential for severe impact.
- Action
- Update to the latest version of affected browsers to address this vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 99% of all EPSS-scored CVEs.
Exploit availability
Public exploit or proof-of-concept code for CVE-2021-21220 is indexed in these free datasets. Available exploit code raises real-world risk independent of the CVSS score.
- MetasploitA Metasploit Framework module targets this CVE — weaponized, point-and-click exploitation.look it up ↗
- GitHub PoCPublic proof-of-concept repositories on GitHub reference this CVE.look it up ↗
Advisory coverage (1)
- criticalexploitedCVE-2021-21220: Google Chromium V8 Improper Input Validation Vulnerabilitycisa-kev · 2021-11-03
External references
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[](https://www.csirts.com/cve/CVE-2021-21220)