CVE-2024-27730
📋 TL;DR
This vulnerability allows remote attackers to bypass authorization checks in Friendica's calendar event feature, potentially accessing sensitive information and executing arbitrary code. All Friendica v.2023.12 installations with the calendar feature enabled are affected.
💻 Affected Systems
- Friendica
📦 What is this software?
Friendica by Friendica
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data exfiltration, and lateral movement within the network.
Likely Case
Unauthorized access to sensitive calendar data and potential privilege escalation within the Friendica application.
If Mitigated
Limited information disclosure if proper network segmentation and access controls are implemented.
🎯 Exploit Status
Exploitation requires authenticated access but authorization bypass makes it accessible to low-privilege users.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v.2024.03 or later
Vendor Advisory: https://github.com/friendica/friendica/pull/13927
Restart Required: Yes
Instructions:
1. Backup your Friendica installation and database. 2. Update to Friendica v.2024.03 or later via git pull or package manager. 3. Run database updates if required. 4. Restart web server services.
🔧 Temporary Workarounds
Disable Calendar Feature
allTemporarily disable the vulnerable calendar feature until patching is possible.
Edit config/local.config.php and add: $a->config['system']['disable_calendar'] = true;
🧯 If You Can't Patch
- Implement strict network access controls to limit Friendica access to trusted users only.
- Enable detailed logging and monitoring for unauthorized calendar event access attempts.
🔍 How to Verify
Check if Vulnerable:
Check Friendica version in admin panel or view source for version string. If version is exactly 2023.12, you are vulnerable.Check Version:
grep -r "FRIENDICA_VERSION" /path/to/friendica/ or check admin dashboardVerify Fix Applied:
Verify version is 2024.03 or later and test calendar event functionality with different user roles.📡 Detection & Monitoring
Log Indicators:
- Unusual calendar event access patterns
- Multiple failed authorization attempts on calendar endpoints
- Unexpected process execution from web server context
Network Indicators:
- Unusual outbound connections from Friendica server
- HTTP requests to calendar endpoints with unexpected cid parameters
SIEM Query:
source="friendica_logs" AND (uri="/calendar/" OR uri="/event/") AND (status=200 OR status=403) | stats count by src_ip, user