Microsoft Patches Actively Exploited SharePoint Zero-Day — How to Identify & Stay Safe

INDIA — By BharatSecure Threat Intelligence Team · Updated Apr 30, 2026

Severity: MEDIUM | View Full Scam Details

Beware in 2026: Microsoft SharePoint Zero-Day Phishing Scam Hits Indian Businesses Hard

A new phishing scam exploiting a Microsoft SharePoint vulnerability is putting Indian businesses and employees at medium risk, with fraudsters actively targeting sensitive data through deceptive messages.

What Is the Microsoft Patches Actively Exploited SharePoint Zero-Day?

This scam stems from a zero-day vulnerability discovered in Microsoft SharePoint, a widely used collaboration and document management tool in India’s corporate and government sectors. Cybercriminals have exploited this security flaw to launch phishing attacks, tricking users into divulging login credentials and sensitive corporate information. These attackers then use this data to compromise accounts or deploy malware.

In India, many organizations rely heavily on Microsoft SharePoint for internal communication and document sharing, making this vulnerability a significant concern. CERT-In (Indian Computer Emergency Response Team) and the Indian Cyber Crime Coordination Centre (I4C) have issued alerts urging businesses to patch systems promptly. The Reserve Bank of India (RBI) also cautions financial institutions to be vigilant, as such breaches can have downstream effects on payment ecosystems like UPI.

The scam has rapidly spread across sectors, including IT firms, financial institutions, and educational bodies in metro cities like Bengaluru, Mumbai, and Hyderabad, with confirmed attempts to harvest credentials from employees via phishing emails linked to the SharePoint zero-day weakness.

How This Scam Works — Step by Step

1. Phishing Email Delivery: Employees receive an email appearing to come from their company’s IT or Microsoft support team, often with authentic-looking logos and sender addresses spoofed using compromised domains.

2. Malicious SharePoint Link: The email contains a link to a SharePoint document or site. Clicking this link redirects victims to a fake login page crafted to mimic Microsoft’s authentication portal.

3. Credential Harvesting: When victims enter their usernames and passwords, the fraudsters capture these details in real-time.

4. Account Takeover: Using stolen credentials, attackers log into corporate SharePoint and associated Microsoft 365 accounts to steal sensitive files or install malware for persistent access.

5. Financial Theft or Data Leakage: With privileged access, they may transfer funds using UPI-linked corporate accounts or leak confidential business data, leading to financial loss and reputation damage.

Real Warning Signs to Watch For

• Unexpected emails urging you to “verify” or “update” SharePoint or Microsoft 365 credentials.
• Email addresses that look similar but have subtle misspellings or odd domain names (for example, microsoft-support.insteadofficial.com).
• Links prompting login but redirecting to pages outside the official microsoft.com domain.
• Urgency language like “Your account will be locked” or “Immediate action required.”
• Poor grammar or spelling mistakes in emails, which official Microsoft or company communications rarely have.
• Unexpected attachments or documents labeled as “Update” or “Security Patch” from unknown senders.
• Login pages that ask for unusual permissions or multiple authentication attempts.

What Happens to Victims

Victims often suffer financial damage directly or indirectly. For Indian corporates, stolen login credentials can lead to unauthorized UPI payments or fund transfers. Given the rising prevalence of Aadhaar-linked bank accounts, criminals may exploit leaked data to conduct SIM swap frauds — intercepting OTPs to approve transactions.

Besides monetary loss, victims often face emotional stress from corporate data breaches, loss of job credibility, and potential legal ramifications. Small businesses, which typically lack strong cybersecurity infrastructure, are particularly vulnerable, potentially leading to irreversible damage or closure.

What RBI and CERT-In Say

RBI has emphasized the importance of securing digital banking platforms and cautions banks to monitor for unauthorized access and fraudulent transactions linked to compromised credentials. They remind users that UPI payments have a limited window for reversal but urge immediate reporting of suspicious activities.

CERT-In has issued advisories to Indian organizations to promptly apply Microsoft’s security patches for SharePoint and to educate staff about phishing risks. The Indian Cyber Crime Coordination Centre (I4C) recommends reporting incidents via the 1930 cybercrime helpline and filing complaints on cybercrime.gov.in to enable tracking and mitigation.

How to Protect Yourself

1. Apply Microsoft’s Latest Security Patch Immediately: Ensure your IT team has installed the April 2026 SharePoint patch.

2. Verify Email Senders Carefully: Double-check official communications with your organization's IT helpdesk before clicking links.

3. Never Enter Credentials on Suspicious Pages: Access SharePoint only via trusted URLs bookmarked by your organization.

4. Enable Multi-Factor Authentication (MFA): Use MFA on all Microsoft accounts to add an extra security layer.

5. Educate Employees: Train staff regularly on spotting phishing attempts and reporting them promptly.

6. Monitor UPI Transactions: Regularly check your organization’s UPI-linked accounts for unusual payments.

7. Use Trusted Antivirus and Endpoint Protection: Detect malware that phishing links might install.

What to Do If You’ve Been Targeted

• Immediately change all compromised passwords and enable MFA.
• Inform your company’s IT security team and block affected accounts to prevent further misuse.
• Report the incident to CERT-In via the 1930 cybercrime helpline and lodge a complaint on cybercrime.gov.in with detailed evidence.
• Contact your bank to monitor or freeze UPI-linked corporate accounts and request transaction reversals if possible.
• If you suspect Aadhaar misuse or SIM swap, reach out to your telecom provider urgently to suspend the SIM and protect your mobile number.
• Maintain documentation of all communications and suspicious messages for official investigation.

Frequently Asked Questions

Q: How do I know if the SharePoint security patch is installed?
A: Contact your IT team or system administrator to confirm that the latest Microsoft update from April 2026 has been applied to all SharePoint servers and user devices.

Q: Can I reverse UPI payments made through compromised accounts?
A: UPI allows payment reversal if reported immediately, but there is no guarantee. Always notify your bank at the earliest sign of unauthorized transactions to improve chances of recovery.

Q: What if I receive a suspicious SharePoint link on WhatsApp or email?
A: Do not click any links. Verify with your IT department, or independently log into SharePoint from a trusted source to check for notifications instead.

If you receive any suspicious messages related to Microsoft, SharePoint, or unusual login prompts, always double-check and verify at BharatSecure.app before clicking or sharing. Stay alert and safe!