CVE-2025-64672
📋 TL;DR
This cross-site scripting (XSS) vulnerability in Microsoft Office SharePoint allows authenticated attackers to inject malicious scripts into web pages, which can then execute in victims' browsers. The vulnerability enables spoofing attacks where attackers can impersonate legitimate users or content. Organizations using affected SharePoint versions are at risk.
💻 Affected Systems
- Microsoft Office SharePoint Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker could steal session cookies, perform actions as authenticated users, redirect to malicious sites, or install malware on user systems through client-side attacks.
Likely Case
Attackers will use this for session hijacking, credential theft, and phishing attacks against SharePoint users by injecting malicious scripts into legitimate pages.
If Mitigated
With proper input validation, output encoding, and Content Security Policy (CSP) headers, the risk is significantly reduced though not eliminated without patching.
🎯 Exploit Status
XSS vulnerabilities typically have low exploitation complexity once the injection point is identified; requires authenticated access to SharePoint
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft Security Update Guide for specific patch versions
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-64672
Restart Required: Yes
Instructions:
1. Review Microsoft Security Update Guide for CVE-2025-64672. 2. Download and install the appropriate security update for your SharePoint version. 3. Restart SharePoint services or the server as required. 4. Test functionality after patching.
🔧 Temporary Workarounds
Implement Content Security Policy
allAdd CSP headers to restrict script execution sources and reduce XSS impact
Input Validation Rules
windowsConfigure SharePoint to validate and sanitize user input before processing
🧯 If You Can't Patch
- Implement strict input validation and output encoding for all user-controlled data
- Use web application firewall (WAF) rules to detect and block XSS payloads
🔍 How to Verify
Check if Vulnerable:
Check SharePoint version against Microsoft's affected versions list when published; test for XSS in user input fieldsCheck Version:
Get-SPFarm | Select BuildVersion (PowerShell) or check Central Administration > Upgrade and Migration > Check product and patch installation statusVerify Fix Applied:
Verify patch installation through Windows Update history or SharePoint version check; test previously vulnerable input fields📡 Detection & Monitoring
Log Indicators:
- Unusual script tags or JavaScript in SharePoint logs
- Multiple failed input validation attempts
- Suspicious user activity patterns
Network Indicators:
- HTTP requests containing suspicious script patterns
- Unexpected redirects from SharePoint pages
SIEM Query:
source="sharepoint*" AND ("<script" OR "javascript:" OR "onerror=" OR "onload=")