Critical

Critical SharePoint RCE CVE-2026-50522 Under Active Exploitation After Public PoC

The Hacker News

July 21, 2026 at 2:57 PM

Actively Exploited

CVE Microsoft Vulnerability Patch Update RCE Critical

Overview

A serious vulnerability in Microsoft SharePoint Server, identified as CVE-2026-50522, is currently being exploited in the wild. This flaw, which has a CVSS score of 9.8, allows attackers to execute arbitrary code on affected systems through deserialization of untrusted data. The vulnerability was patched by Microsoft during its July 2026 Patch Tuesday update but has since been targeted by malicious actors. Organizations using SharePoint need to prioritize applying the latest security updates to protect against potential unauthorized access and exploitation. It's crucial for administrators to stay vigilant and monitor their systems for any signs of compromise.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Microsoft Office SharePoint Server
Action Required: Organizations should apply the security patches provided by Microsoft in the July 2026 Patch Tuesday update to mitigate this vulnerability.
Timeline: Disclosed on July 2026

Original Article Summary

A third SharePoint Server flaw patched by Microsoft as part of its Patch Tuesday update for July 2026 has come under active exploitation, per watchTowr. The vulnerability in question is CVE-2026-50522 (CVSS score: 9.8), a critical deserialization of untrusted data in Microsoft Office SharePoint that could allow an unauthorized attacker to execute code over a network. Microsoft credited DEVCORE

Impact

Microsoft Office SharePoint Server

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Disclosed on July 2026

Remediation

Organizations should apply the security patches provided by Microsoft in the July 2026 Patch Tuesday update to mitigate this vulnerability.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Microsoft, Vulnerability, and 4 more.

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