Authenticated spoofing via unsafe deserialization
Published Aug 11, 2026 · Updated Aug 25, 2026
Deserialization of untrusted data in Microsoft Office SharePoint allows remote authenticated users to spoof trusted data over a network. Public records disclose only that SharePoint accepts and deserializes attacker-controlled data; they do not identify the affected handler, object type, or trust check that fails. Low-privileged authenticated access is required, and published scoring bounds the consequence to spoofing and confidentiality exposure rather than code execution or service interruption.
Summary
What happened
Deserialization of untrusted data in Microsoft Office SharePoint allows remote authenticated users to spoof trusted data over a network. Public records disclose only that SharePoint accepts and deserializes attacker-controlled data; they do not identify the affected handler, object type, or trust check that fails. Low-privileged authenticated access is required, and published scoring bounds the consequence to spoofing and confidentiality exposure rather than code execution or service interruption.
The record
- CVE
- CVE-2026-63516
- Published
- Aug 11, 2026
- Updated
- Aug 25, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-502
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 11, 2026CVE publishedPublication date reported by the CVE source.
- Aug 25, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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