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

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.

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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

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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

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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

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🛡️ 2. Enable SameSite Cookie Attribute

• Set cookies to:

            SameSite=Strict or SameSite=Lax

• Prevents cookies from being sent with cross-site requests

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🔑 3. Require Re-Authentication for Critical Actions

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

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🌐 4. Validate HTTP Request Headers

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

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🔄 5. Apply Security Patches

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

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📊 6. Monitor and Log User Activity

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

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👥 7. User Awareness & Training

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

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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.

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