CVE-2021-38003: in the CISA KEV catalogue
Google Chromium V8 Memory Corruption Vulnerability. CISA added CVE-2021-38003 to the Known Exploited Vulnerabilities catalogue on 2021-11-03 with a default due date of 2021-11-17. Known ransomware campaign use: Unknown. Forensic triage flag: No.
Google Chromium V8 Engine has a bug in JSON.stringify, where the internal TheHole value can leak to script code, causing memory corruption. This vulnerability could affect multiple web browsers that utilize Chromium, including, but not limited to, Google Chrome, Microsoft Edge, and Opera. (CISA description)
- Vendor / product
- Google Chromium V8
- CWE
- CWE-122, CWE-755
- CISA required action
- Apply updates per vendor instructions.
- EPSS
- 39%, percentile 98 (scored 2026-11-03)
EPSS puts about 39 in 100 odds (39%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 98% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2021-38003 in the CISA KEV catalogue?
Yes. CISA added CVE-2021-38003 (Google Chromium V8 Memory Corruption Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2021-11-03. CISA's default due date for it is 2021-11-17.
Is CVE-2021-38003 used in ransomware attacks?
CISA marks known ransomware campaign use as Unknown for CVE-2021-38003. That means CISA lacks confirmation, not that ransomware groups do not use it.
What should I do about CVE-2021-38003?
CISA's required action: Apply updates per vendor instructions.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2021-38003