Microsoft has disclosed that multiple China-linked cyber espionage groups, including Linen Typhoon, Violet Typhoon, and Storm-2603, have exploited vulnerabilities in on-premises SharePoint servers. These attacks compromised sensitive data from organizations across various global sectors, raising significant cybersecurity concerns and prompting urgent updates from Microsoft.
What Happened in the Microsoft SharePoint Server Breach?
Microsoft has revealed that several state-sponsored Chinese threat actors exploited security flaws in on-premises SharePoint servers—the versions typically used by enterprises rather than Microsoft’s cloud-based infrastructure. These attacks targeted sensitive data and allowed the attackers to gain unauthorized access by extracting cryptographic key material.
Who Are the Groups Behind the Attacks?
Linen Typhoon
Active for over a decade, Linen Typhoon is linked to Chinese state-backed cyber espionage operations. Microsoft reports the group primarily targets:
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Government agencies
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Defense contractors
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Strategic think tanks
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Human rights organizations
Their intent appears to be focused on intellectual property theft and strategic intelligence gathering.
Violet Typhoon
Described as an espionage-focused group, Violet Typhoon has aimed its attacks at:
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Former government and military personnel
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NGOs and think tanks
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Academic institutions
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Media outlets
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Financial and healthcare organizations
Their operations span across the United States, Europe, and East Asia.
Storm-2603
Storm-2603 is assessed with medium confidence to be a China-based hacking entity. While less is known about this group, it was actively involved in exploiting the same SharePoint vulnerabilities.
How Did the Exploit Work?
Microsoft’s investigation revealed that attackers sent specific requests to vulnerable SharePoint servers, which enabled the theft of cryptographic keys. Once stolen, these keys allowed persistent access to SharePoint data—essentially unlocking sensitive files without detection.
Charles Carmakal, CTO of Mandiant Consulting (a Google Cloud company), stated the attack had far-reaching implications, affecting multiple industries across various global regions.
He emphasized the broad and opportunistic nature of the campaign, noting that it was executed before a patch was publicly available, making it particularly damaging.
Who Was Affected?
The UK’s National Cyber Security Centre (NCSC) confirmed that a limited number of SharePoint Server users in the UK were impacted. However, according to Mandiant, the targets spanned:
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Government institutions
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Global enterprises
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International infrastructure entities
Affected organizations relied on on-premises SharePoint setups, making them especially vulnerable.
How Is Microsoft Responding?
Microsoft has released critical security updates for all on-premises SharePoint server users and strongly urges immediate installation to prevent further breaches.
🚨 Microsoft warns: Systems that have not been updated remain highly vulnerable.
The company has high confidence that threat actors will continue exploiting unpatched systems. It is still investigating other potential actors using the same vulnerabilities and is updating its official blog as new findings emerge.
How Did China Respond?
In response to Microsoft’s findings, Liu Pengyu, a spokesperson for China’s U.S. Embassy, issued a statement:
“China firmly opposes and combats all forms of cyberattacks and cybercrime. At the same time, we also firmly oppose smearing others without solid evidence.”
This reflects Beijing’s continued denial of involvement in international cyber-espionage campaigns, despite growing global attribution to Chinese-based groups.
What’s the Broader Impact on Businesses and Digital Trust?
This breach highlights the critical importance of maintaining updated infrastructure—especially for on-premises solutions. For businesses relying on organic channels to build visibility and authority, such breaches can harm brand trust, data security, and ultimately impact organic search engine rankings if customer confidence is lost.
Cyber incidents also damage long-term SEO performance by affecting site reliability, reputation, and overall web presence. For enterprise websites running on outdated tech stacks, this event serves as a reminder to prioritize cybersecurity as part of digital optimization strategies.
Final Thoughts
The Microsoft SharePoint breach, attributed to sophisticated China-based cyber operations, serves as a powerful reminder of the evolving digital threat landscape. As companies increasingly rely on digital ecosystems to power operations and drive organic search engine rankings, proactive security hygiene is no longer optional—it’s mission-critical.
