CVE-2025-64667
📋 TL;DR
This CVE describes a UI spoofing vulnerability in Microsoft Exchange Server where an unauthorized attacker can manipulate the user interface to misrepresent critical information over a network. This could trick users into performing unintended actions. Organizations running vulnerable Microsoft Exchange Server versions are affected.
💻 Affected Systems
- Microsoft Exchange Server
📦 What is this software?
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
Exchange Server by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
An attacker could spoof critical security warnings or authentication prompts, tricking administrators into disabling security controls or revealing credentials, potentially leading to full Exchange Server compromise.
Likely Case
Attackers could create convincing phishing interfaces within Exchange to harvest user credentials or trick users into downloading malware.
If Mitigated
With proper user awareness training and multi-factor authentication, the impact is reduced to minor inconvenience or failed phishing attempts.
🎯 Exploit Status
The vulnerability requires network access but no authentication. Exploitation involves crafting malicious UI elements rather than complex code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not yet released
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-64667
Restart Required: Yes
Instructions:
1. Monitor Microsoft Security Response Center for patch release. 2. Apply security update through Windows Update or Microsoft Update Catalog. 3. Restart Exchange Server services as required.
🔧 Temporary Workarounds
Restrict network access
allLimit access to Exchange Server to trusted networks only
Configure firewall rules to restrict inbound connections to Exchange Server
User awareness training
allTrain users to verify URLs and be cautious of unexpected authentication prompts
🧯 If You Can't Patch
- Implement network segmentation to isolate Exchange Server from untrusted networks
- Enable multi-factor authentication for all Exchange administrative and user accounts
🔍 How to Verify
Check if Vulnerable:
Check Exchange Server version against Microsoft's advisory when publishedCheck Version:
Get-ExchangeServer | Format-List Name, Edition, AdminDisplayVersionVerify Fix Applied:
Verify Exchange Server version matches patched version in Microsoft advisory📡 Detection & Monitoring
Log Indicators:
- Unusual authentication attempts from unexpected locations
- Multiple failed login attempts followed by successful login
Network Indicators:
- Unusual HTTP requests to Exchange UI endpoints
- Suspicious redirects or iframe injections
SIEM Query:
source="Exchange" AND (event_id=4625 OR event_id=4648) | stats count by src_ip