CVE-2021-21166
Actively exploited. CVE-2021-21166 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.
Google Chromium contains a race condition 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 contains a race condition vulnerability that may lead to heap corruption.
- Who is affected
- Users of web browsers utilizing Chromium are affected.
- Urgency
- This critical vulnerability is actively exploited, requiring urgent remediation.
- Action
- Update to the latest version of Chromium or affected browsers.
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 98% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2021-21166: Google Chromium Race Condition Vulnerabilitycisa-kev · 2021-11-03
External references
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