CVE-2025-55521
📋 TL;DR
An authenticated attacker can send a specially crafted POST request to the /settings/localisation endpoint in Akaunting v3.1.18, causing a Denial of Service (DoS) that makes the application unavailable. This affects all organizations running the vulnerable version of Akaunting with authenticated user access.
💻 Affected Systems
- Akaunting
📦 What is this software?
Akaunting by Akaunting
⚠️ Risk & Real-World Impact
Worst Case
Complete application unavailability requiring service restart, potentially disrupting business operations and financial management.
Likely Case
Temporary service disruption affecting authenticated users until the application is restarted or the attack stops.
If Mitigated
Minimal impact with proper rate limiting, request validation, and monitoring in place.
🎯 Exploit Status
Requires authenticated access and knowledge of the vulnerable endpoint. The specific payload details are not publicly documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v3.1.19 or later
Vendor Advisory: https://github.com/akaunting/akaunting
Restart Required: No
Instructions:
1. Backup your Akaunting installation and database. 2. Update Akaunting to version 3.1.19 or later via the built-in updater or manual installation. 3. Verify the update completed successfully.
🔧 Temporary Workarounds
Restrict access to /settings/localisation
allBlock or restrict access to the vulnerable endpoint using web server configuration or application firewalls.
# Example for Apache: RewriteRule ^/settings/localisation - [F]
# Example for Nginx: location ~ ^/settings/localisation { deny all; }
Implement rate limiting
allApply rate limiting to POST requests to prevent DoS attacks.
# Example using fail2ban or similar tools
# Configure web server rate limiting modules
🧯 If You Can't Patch
- Implement strict authentication controls and monitor for unusual POST requests to /settings/localisation.
- Deploy a web application firewall (WAF) with DoS protection rules.
🔍 How to Verify
Check if Vulnerable:
Check the Akaunting version in the admin dashboard or via the application's version file.Check Version:
Check the admin dashboard or view the version in the application's configuration files.Verify Fix Applied:
Confirm the version is 3.1.19 or later and test that POST requests to /settings/localisation no longer cause service disruption.📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /settings/localisation from single authenticated users
- Application error logs showing service disruption
Network Indicators:
- Unusual spike in POST request volume to the vulnerable endpoint
SIEM Query:
source="web_server_logs" AND uri="/settings/localisation" AND method="POST" AND status=200 | stats count by src_ip