CVE-2023-41704
📋 TL;DR
This CVE-2023-41704 is a cross-site scripting (XSS) vulnerability in Open-Xchange AppSuite email processing. Attackers can inject malicious scripts through CID references in emails, which bypass sanitization and execute in users' sessions when they interact with emails. Organizations using vulnerable Open-Xchange AppSuite versions are affected.
💻 Affected Systems
- Open-Xchange AppSuite
📦 What is this software?
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
Open Xchange Appsuite by Open Xchange
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal session cookies, perform actions as authenticated users, or redirect users to malicious sites, potentially leading to account compromise and data theft.
Likely Case
Attackers would typically use this to steal session cookies or credentials from users who open malicious emails, leading to unauthorized access to email accounts.
If Mitigated
With proper email filtering and user awareness training, the risk is reduced to isolated incidents affecting individual users rather than system-wide compromise.
🎯 Exploit Status
Exploitation requires sending malicious emails to users. No public exploits are known, but the vulnerability is straightforward to exploit once understood.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patch Release 6259 (7.10.6)
Vendor Advisory: https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/oxas-adv-2023-0007.json
Restart Required: Yes
Instructions:
1. Download patch release 6259 from Open-Xchange. 2. Apply the patch following Open-Xchange AppSuite update procedures. 3. Restart the AppSuite services. 4. Verify the update was successful.
🔧 Temporary Workarounds
Email Content Filtering
allImplement email filtering to block or sanitize CID references in incoming emails
Disable HTML Email Rendering
allConfigure email clients to display emails in plain text only
🧯 If You Can't Patch
- Implement strict email filtering to block suspicious CID references
- Educate users about email security risks and warn against opening suspicious emails
🔍 How to Verify
Check if Vulnerable:
Check if Open-Xchange AppSuite version is earlier than patch release 6259 (7.10.6)Check Version:
Check AppSuite version through admin interface or configuration filesVerify Fix Applied:
Verify the system is running patch release 6259 or later and test email processing with test CID references📡 Detection & Monitoring
Log Indicators:
- Unusual email processing errors
- Multiple failed email parsing attempts
- Suspicious CID reference patterns in email logs
Network Indicators:
- Unusual email traffic patterns
- Multiple emails with similar CID references from single sources
SIEM Query:
Search for email processing errors or suspicious CID patterns in email server logs🔗 References
- https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/oxas-adv-2023-0007.json
- https://software.open-xchange.com/products/appsuite/doc/Release_Notes_for_Patch_Release_6259_7.10.6_2023-12-11.pdf
- http://seclists.org/fulldisclosure/2024/Feb/10
- https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/oxas-adv-2023-0007.json
- https://software.open-xchange.com/products/appsuite/doc/Release_Notes_for_Patch_Release_6259_7.10.6_2023-12-11.pdf
