CVE-2023-4047
📋 TL;DR
This vulnerability allows attackers to manipulate popup notification timing in Firefox browsers, tricking users into granting unintended permissions. It affects Firefox versions before 116, Firefox ESR before 102.14, and Firefox ESR before 115.1. Attackers could exploit this to gain permissions for actions like accessing cameras, microphones, or location data.
💻 Affected Systems
- Mozilla Firefox
- Mozilla Firefox ESR
📦 What is this software?
Firefox by Mozilla
Firefox by Mozilla
Firefox by Mozilla
⚠️ Risk & Real-World Impact
Worst Case
Attackers gain persistent access to sensitive device permissions (camera, microphone, location) leading to privacy violations, surveillance, or credential theft through social engineering.
Likely Case
Users inadvertently grant permissions to malicious websites, enabling limited data collection or unwanted actions without their knowledge.
If Mitigated
With updated browsers and user awareness, exploitation attempts fail as the timing manipulation is prevented and users are more cautious with permission prompts.
🎯 Exploit Status
Exploitation requires user interaction (clicking on malicious content) but timing manipulation makes it easier to trick users.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firefox 116, Firefox ESR 102.14, Firefox ESR 115.1
Vendor Advisory: https://bugzilla.mozilla.org/show_bug.cgi?id=1839073
Restart Required: Yes
Instructions:
1. Open Firefox. 2. Click the menu button (three horizontal lines). 3. Select Help > About Firefox. 4. Firefox will check for updates and install them automatically. 5. Restart Firefox when prompted.
🔧 Temporary Workarounds
Disable automatic permission grants
allConfigure Firefox to require explicit user action for all permission requests, reducing the risk of accidental grants.
about:config
Set permissions.default.* to false (e.g., permissions.default.camera = false)
Use browser extensions to block permission prompts
allInstall extensions that block or manage permission requests from websites.
🧯 If You Can't Patch
- Educate users to be cautious with permission prompts and avoid clicking on suspicious links.
- Implement network filtering to block known malicious websites that might exploit this vulnerability.
🔍 How to Verify
Check if Vulnerable:
Check Firefox version in About Firefox (menu > Help > About Firefox). If version is below 116 (or ESR below 102.14/115.1), it is vulnerable.Check Version:
firefox --version (Linux/macOS) or check via browser interface on all platformsVerify Fix Applied:
After updating, verify the version is at least Firefox 116, Firefox ESR 102.14, or Firefox ESR 115.1 in About Firefox.📡 Detection & Monitoring
Log Indicators:
- Unusual permission grants in browser logs or security event logs, especially from untrusted websites.
Network Indicators:
- Traffic to known malicious domains that might host exploit code.
SIEM Query:
Search for browser events where permissions (camera, microphone, location) are granted unexpectedly or from suspicious sources.🔗 References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1839073
- https://lists.debian.org/debian-lts-announce/2023/08/msg00008.html
- https://lists.debian.org/debian-lts-announce/2023/08/msg00010.html
- https://www.debian.org/security/2023/dsa-5464
- https://www.debian.org/security/2023/dsa-5469
- https://www.mozilla.org/security/advisories/mfsa2023-29/
- https://www.mozilla.org/security/advisories/mfsa2023-30/
- https://www.mozilla.org/security/advisories/mfsa2023-31/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1839073
- https://lists.debian.org/debian-lts-announce/2023/08/msg00008.html
- https://lists.debian.org/debian-lts-announce/2023/08/msg00010.html
- https://www.debian.org/security/2023/dsa-5464
- https://www.debian.org/security/2023/dsa-5469
- https://www.mozilla.org/security/advisories/mfsa2023-29/
- https://www.mozilla.org/security/advisories/mfsa2023-30/
- https://www.mozilla.org/security/advisories/mfsa2023-31/
