CVE-2021-21220
Out-of-bounds Write
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Description
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.
Official description from the CVE record, published by Chrome. Copyright © 1999-2026 The MITRE Corporation. See /security/cve/legal for the CVE license. View the record on cve.org
Key data
CVSS 3.1 High 8.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: None
No account or privileges are needed.
User interaction: Required
A user has to do something first, such as opening a file or following a link.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: High
Serious or total effect on the secrecy of data.
Integrity impact: High
Serious or total effect on the trustworthiness of data.
Availability impact: High
Serious or total effect on availability.
| Metric | Value | What it means |
|---|---|---|
| Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity | Low | No special conditions are needed. The attack can be repeated at will. |
| Privileges required | None | No account or privileges are needed. |
| User interaction | Required | A user has to do something first, such as opening a file or following a link. |
| Scope | Unchanged | The impact stays within the vulnerable component. |
| Confidentiality impact | High | Serious or total effect on the secrecy of data. |
| Integrity impact | High | Serious or total effect on the trustworthiness of data. |
| Availability impact | High | Serious or total effect on availability. |
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EPSS
- Score
- 0.70435 (70.4% probability)
- Percentile
- 99.4%
- Scores of
- Nov 10, 2026
- Model
- v2026.06.15
CISA Known Exploited Vulnerabilities
- Name in the catalog
- Google Chromium V8 Improper Input Validation Vulnerability
- Added to the catalog
- Nov 3, 2021
- Federal due date
- Nov 17, 2021
CISA assessment as of Feb 5, 2024
- Exploitation
- Recorded by CISA as active
- Automatable
- no
- Technical impact
- total
Weakness (CWE)
- CWE-787Out-of-bounds Write
Affected products
Google Chrome
- affected: unspecified up to before 89.0.4389.128
References
- chromereleases.googleblog.com/2021/04/stable-channel-update…
- crbug.com/1196683
- GLSA-202104-08 (security.gentoo.org)vendor-advisory
- packetstormsecurity.com/files/162437/Google-Chrome-XOR-Type…
- FEDORA-2021-c3754414e7 (lists.fedoraproject.org)vendor-advisory
- FEDORA-2021-ff893e12c5 (lists.fedoraproject.org)vendor-advisory
- FEDORA-2021-35d2bb4627 (lists.fedoraproject.org)vendor-advisory
- packetstormsecurity.com/files/176210/Chrome-V8-JIT-XOR-Arbi…
Timeline
- ID reserved
- Record published
- Added to CISA KEV
- Record last updated
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About CubePath
Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:36 UTC. Sources and licenses