CVE-2025-15366
📋 TL;DR
CVE-2025-15366 is a command injection vulnerability in Python's imaplib module where user-controlled commands containing newlines can inject additional IMAP commands. This affects any Python application using imaplib with untrusted input. The vulnerability allows attackers to manipulate IMAP sessions and potentially access email data.
💻 Affected Systems
- Python
- Applications using Python's imaplib module
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Full compromise of IMAP email accounts, allowing attackers to read, delete, or send emails as the victim, potentially leading to data theft, account takeover, or further phishing attacks.
Likely Case
Unauthorized access to email content, manipulation of mailbox contents, or disclosure of sensitive information from the affected email account.
If Mitigated
Limited impact with proper input validation and command sanitization in place, restricting attackers to only authorized IMAP operations.
🎯 Exploit Status
Exploitation requires the ability to control input to imaplib commands, typically requiring some level of application access or user interaction.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Python versions with commit 6262704b134db2a4ba12e85ecfbd968534f28b45
Vendor Advisory: https://mail.python.org/archives/list/security-announce@python.org/thread/DD7C7JZJYTBXMDOWKCEIEBJLBRU64OMR/
Restart Required: No
Instructions:
1. Update Python to a version containing the fix commit 6262704b134db2a4ba12e85ecfbd968534f28b45. 2. No application restart required for Python updates, but restart applications to load the updated Python interpreter.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement strict input validation to reject commands containing control characters (especially newlines) before passing to imaplib.
# Example Python code to sanitize input
import re
def sanitize_imap_command(cmd):
# Remove control characters
return re.sub(r'[\x00-\x1F\x7F]', '', cmd)
🧯 If You Can't Patch
- Implement strict input validation in application code to reject any user input containing control characters before passing to imaplib functions.
- Use allow-lists for IMAP commands and parameters rather than passing raw user input directly to imaplib.
🔍 How to Verify
Check if Vulnerable:
Check if your Python application passes user-controlled input to imaplib commands without validating for control characters.Check Version:
python --versionVerify Fix Applied:
Verify Python version includes commit 6262704b134db2a4ba12e85ecfbd968534f28b45 by checking the commit history or version details.📡 Detection & Monitoring
Log Indicators:
- Unusual IMAP command sequences in application logs
- Multiple IMAP commands in single requests
- IMAP errors related to invalid commands
Network Indicators:
- Unusual IMAP traffic patterns
- Multiple IMAP commands in single packets
SIEM Query:
Search for application logs containing imaplib errors or unusual command sequences with control characters.