:::: MENU ::::

February 8, 2026

  • February 08, 2026

Explanation of the Image: CSRF – CVE-2020-12116 (SharePoint Web Interface)

  • The image represents a Cross-Site Request Forgery (CSRF) attack targeting the SharePoint web interface.
  • It shows a logged-in victim user unknowingly triggering malicious requests while browsing a malicious website.
  • The attacker exploits the victim’s authenticated SharePoint session to perform unauthorized actions.
  • The SharePoint server trusts the request because it contains valid session cookies.
    • Unauthorized operations may include:

      Modifying SharePoint settings
    • Uploading or deleting files
    • Changing permissions
    • Triggering workflows
  • The attack occurs without stealing credentials, making it difficult for users to detect.
  • The image highlights the flow of unauthorized requests from a malicious site to SharePoint.
  • Warning symbols and shields emphasize the security risk and lack of proper request validation.
  • The CVE identifier (CVE-2020-12116) indicates a known and documented vulnerability.


How the CSRF Attack Works (Step-by-Step)

  1. User logs into SharePoint (session cookie is stored in browser)
  2. User visits a malicious website
  3. Malicious site sends a hidden request to SharePoint
  4. Browser automatically attaches SharePoint session cookies
  5. SharePoint executes the request as a legitimate user action
  6. Unauthorized changes occur without user awareness


Impact of the Attack

  • Unauthorized configuration changes
  • Data manipulation or deletion
  • Privilege escalation
  • Compromise of business workflows
  • Loss of data integrity and trust
  • Regulatory and compliance risks


Protection and Mitigation Measures

🔐 1. Implement Anti-CSRF Tokens

  • Use unique, unpredictable CSRF tokens in all sensitive requests
  • Validate tokens on the server side
  • Reject requests without valid tokens


🛡️ 2. Enable SameSite Cookie Attribute

  • Set cookies to:
            SameSite=Strict or SameSite=Lax
  • Prevents cookies from being sent with cross-site requests

🔑 3. Require Re-Authentication for Critical Actions

  • Force users to re-enter credentials for:
    • Permission changes
    • Administrative actions
    • Configuration updates


🌐 4. Validate HTTP Request Headers

  • Verify:
    • Origin
    • Referer
  • Reject requests from untrusted domains


🔄 5. Apply Security Patches

  • Install Microsoft patches addressing CVE-2020-12116
  • Keep SharePoint and IIS fully up to date


📊 6. Monitor and Log User Activity

  • Enable detailed logging for:
    • Permission changes
    • Administrative actions
  • Alert on abnormal request patterns

👥 7. User Awareness & Training

  • Educate users about:
    • Phishing websites
    • Suspicious links
    • Unexpected behavior while logged in


Key Takeaway

Cross-Site Request Forgery exploits trust in authenticated sessions, not stolen credentials. CVE-2020-12116 demonstrates how inadequate request validation in SharePoint can allow attackers to perform unauthorized actions silently.

Strong request validation, token enforcement, and secure cookie configurations are essential to preventing CSRF attacks.