CVE-2018-12397
Mozilla: WebExtension local file permission check bypass
Severity
ModerateRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · October 23, 2018
Updated · January 14, 2026
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.0 · 7.1CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CWE-862 · Missing Authorization