CVE-2025-57733
📋 TL;DR
This CVE describes an SMTP injection vulnerability in JetBrains TeamCity that allows attackers to modify email content sent by the application. Attackers could potentially alter email headers, body content, or recipients. This affects all organizations running vulnerable versions of TeamCity.
💻 Affected Systems
- JetBrains TeamCity
📦 What is this software?
Teamcity by Jetbrains
⚠️ Risk & Real-World Impact
Worst Case
Attackers could modify email content to include malicious links, alter recipient addresses to redirect sensitive communications, or inject malicious content that appears legitimate from the organization.
Likely Case
Attackers modify email content to include phishing links or redirect password reset emails, potentially leading to credential theft or social engineering attacks.
If Mitigated
With proper email validation and sanitization controls, the impact is limited to minor email formatting issues or failed email delivery.
🎯 Exploit Status
Exploitation requires access to modify email parameters, likely through authenticated access or another vulnerability chain.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2025.07.1 or later
Vendor Advisory: https://www.jetbrains.com/privacy-security/issues-fixed/
Restart Required: No
Instructions:
1. Backup your TeamCity configuration and data. 2. Download TeamCity 2025.07.1 or later from the JetBrains website. 3. Follow the TeamCity upgrade documentation for your deployment method. 4. Verify the upgrade completed successfully.
🔧 Temporary Workarounds
Disable email notifications
allTemporarily disable all email notifications in TeamCity to prevent exploitation of the SMTP injection vulnerability.
Navigate to TeamCity Administration > Notifications > Disable all email notifications
Implement email content validation
allAdd input validation for all email-related fields to prevent injection attempts.
Configure TeamCity to validate email content using built-in validation rules or custom scripts
🧯 If You Can't Patch
- Implement network segmentation to restrict TeamCity server access to only authorized users and systems
- Enable detailed logging for all email sending activities and monitor for unusual patterns
🔍 How to Verify
Check if Vulnerable:
Check your TeamCity version in the Administration > Server Administration page. If version is below 2025.07.1, you are vulnerable.Check Version:
Check TeamCity web interface: Administration > Server Administration > Version InformationVerify Fix Applied:
After upgrading, verify the version shows 2025.07.1 or higher and test email notifications to ensure they function correctly without injection.📡 Detection & Monitoring
Log Indicators:
- Unusual email content patterns in TeamCity logs
- Multiple failed email sending attempts with modified content
- Log entries showing email parameter manipulation
Network Indicators:
- Unusual SMTP traffic patterns from TeamCity server
- Email content containing unexpected headers or injection attempts
SIEM Query:
source="teamcity" AND ("email" OR "smtp") AND ("injection" OR "modif" OR "malicious")