CVE-2021-41916
📋 TL;DR
A CSRF vulnerability in webTareas version 2.4 and earlier allows attackers to trick authenticated administrators into unknowingly creating new administrative profiles and adding users to them. This affects all webTareas installations running vulnerable versions where administrators access the web interface.
💻 Affected Systems
- webTareas
📦 What is this software?
Webtareas by Webtareas Project
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the webTareas instance with attacker-controlled administrative accounts gaining full access to all data and functionality.
Likely Case
Unauthorized administrative accounts created, potentially leading to data theft, privilege escalation, or further system compromise.
If Mitigated
Limited impact with proper CSRF protections, though administrative actions could still be performed if user is tricked.
🎯 Exploit Status
Exploitation requires tricking an authenticated administrator to visit a malicious webpage. The vulnerability is well-documented in public advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available. Upgrade to version 2.5 or later if available, or implement workarounds.
🔧 Temporary Workarounds
Implement CSRF Tokens
allAdd CSRF protection tokens to all state-changing requests in webTareas
Manual code modification required - add CSRF tokens to forms and validate them server-side
SameSite Cookie Attribute
allSet SameSite=Strict or SameSite=Lax attributes on session cookies
Set-Cookie: session=value; SameSite=Strict; Secure; HttpOnly
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to detect and block CSRF attempts
- Restrict administrator access to trusted networks only and implement strict access controls
🔍 How to Verify
Check if Vulnerable:
Check webTareas version in admin panel or configuration files. If version is 2.4 or earlier, system is vulnerable.Check Version:
Check admin panel or examine webTareas configuration files for version informationVerify Fix Applied:
Test CSRF protection by attempting to perform administrative actions without valid CSRF tokens. Requests should be rejected.📡 Detection & Monitoring
Log Indicators:
- Multiple administrative profile creations from same session
- User creation events without corresponding admin login events
- Unusual administrative actions from unexpected IP addresses
Network Indicators:
- HTTP POST requests to administrative endpoints without Referer headers or with external Referers
- Requests containing administrative actions from non-administrative IPs
SIEM Query:
source="webtareas" AND (event="create_profile" OR event="add_user") | stats count by src_ip, user