Firefox must be configured to prevent JavaScript from raising or lowering windows.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-251555 | FFOX-00-000011 | SV-251555r1067556_rule | CCI-000381 | medium |
| Description | ||||
| JavaScript can raise and lower browser windows to cause improper input. Configure the browser setting to prevent scripts on visited websites from raising and lowering browser windows. | ||||
| STIG | Date | |||
| Mozilla Firefox Security Technical Implementation Guide | 2025-02-11 | |||
Details
Check Text (C-251555r1067556_chk)
Type "about:policies" in the browser address bar.
If "Preferences" is not displayed under Policy Name or the Policy Value does not include "dom.disable_window_flip" with a value of "true" and status of "locked", this is a finding.
Fix Text (F-54944r807136_fix)
Windows group policy:
1. Open the group policy editor tool with "gpedit.msc".
2. Navigate to Policy Path: Computer Configuration\Administrative Templates\Mozilla\Firefox\
Policy Name: Preferences
Policy State: Enabled
Policy Value:
{
"dom.disable_window_flip": {
"Value": true,
"Status": "locked"
}
}
macOS "plist" file:
Add the following:
<key>Preferences</key>
<dict>
<key>dom.disable_window_flip</key>
<dict>
<key>Value</key>
<true/>
<key>Status</key>
<string>locked</string>
</dict>
</dict>
Linux "policies.json" file:
Add the following in the policies section:
"Preferences": {
"dom.disable_window_flip": {
"Value": true,
"Status": "locked"
}
}