CVE-2025-1940
📋 TL;DR
This vulnerability allows attackers to partially obscure confirmation prompts in Firefox for Android, tricking users into launching external apps unexpectedly. It affects Android users running Firefox versions below 136, potentially leading to unauthorized app launches.
💻 Affected Systems
- Firefox for Android
📦 What is this software?
Firefox by Mozilla
⚠️ Risk & Real-World Impact
Worst Case
User unknowingly launches malicious external app that compromises device security or steals sensitive data
Likely Case
User accidentally launches legitimate external app due to obscured prompt, causing minor inconvenience
If Mitigated
No impact if users are trained to verify prompts carefully or if prompt blocking is enabled
🎯 Exploit Status
Exploitation requires user interaction with malicious web content; no authentication bypass needed
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firefox 136
Vendor Advisory: https://www.mozilla.org/security/advisories/mfsa2025-14/
Restart Required: Yes
Instructions:
1. Open Google Play Store 2. Search for Firefox 3. Update to version 136 or higher 4. Restart Firefox after update
🔧 Temporary Workarounds
Disable external app launching
androidPrevent Firefox from launching external apps entirely
about:config → search 'intent' → set 'dom.intent.enabled' to false
Use desktop mode
androidSwitch to desktop view mode which may not trigger the vulnerable prompt
Tap menu → Request Desktop Site
🧯 If You Can't Patch
- Train users to carefully inspect confirmation prompts before accepting
- Use alternative browsers until Firefox can be updated
🔍 How to Verify
Check if Vulnerable:
Open Firefox → Menu → Settings → About Firefox → Check version numberCheck Version:
about:Verify Fix Applied:
Confirm Firefox version is 136 or higher in About Firefox section📡 Detection & Monitoring
Log Indicators:
- Unusual external app launches from Firefox
- Multiple prompt acceptances in short time
Network Indicators:
- Requests to known malicious domains followed by app launches
SIEM Query:
source="firefox" AND event="app_launch" AND user_interaction="prompt"