CVE-2025-3032
📋 TL;DR
This vulnerability allows file descriptors from the fork server to leak into web content processes, potentially enabling privilege escalation attacks. It affects Firefox versions before 137 and Thunderbird versions before 137, allowing attackers to gain elevated privileges on affected systems.
💻 Affected Systems
- Firefox
- Thunderbird
📦 What is this software?
Firefox by Mozilla
Thunderbird by Mozilla
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise through privilege escalation leading to arbitrary code execution with elevated privileges.
Likely Case
Local privilege escalation allowing attackers to execute code with higher privileges than intended.
If Mitigated
Limited impact with proper sandboxing and privilege separation in place.
🎯 Exploit Status
Exploitation requires local access and knowledge of the file descriptor leak mechanism.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firefox 137, Thunderbird 137
Vendor Advisory: https://www.mozilla.org/security/advisories/mfsa2025-20/
Restart Required: Yes
Instructions:
1. Open Firefox/Thunderbird. 2. Go to Help > About Firefox/Thunderbird. 3. Allow automatic update to version 137 or higher. 4. Restart the application.
🔧 Temporary Workarounds
Disable vulnerable applications
allTemporarily disable Firefox and Thunderbird until patched.
🧯 If You Can't Patch
- Restrict user access to systems with vulnerable versions.
- Implement application whitelisting to prevent execution of vulnerable browsers.
🔍 How to Verify
Check if Vulnerable:
Check Firefox/Thunderbird version in Help > About. If version is below 137, system is vulnerable.Check Version:
firefox --version or thunderbird --versionVerify Fix Applied:
Confirm version is 137 or higher in Help > About.📡 Detection & Monitoring
Log Indicators:
- Unusual process privilege escalation
- File descriptor manipulation attempts
Network Indicators:
- Local privilege escalation attempts
SIEM Query:
Process creation events with unexpected parent-child relationships or privilege changes