Microsoft SharePoint Server 2.0/16.0.5548.1003 deserialization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Microsoft SharePoint Server. This issue affects some unknown processing. This manipulation causes deserialization. The identification of this vulnerability is CVE-2026-35439. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Microsoft SharePoint Server. Affected by this vulnerability is some unknown functionality. The manipulation with an unknown input leads to a deserialization vulnerability. The CWE definition for the vulnerability is CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was shared 05/12/2026 as confirmed security update guide (Website). The advisory is shared at msrc.microsoft.com. This vulnerability is known as CVE-2026-35439. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/13/2026).

The vulnerability scanner Nessus provides a plugin with the ID 314345 (Security Updates for Microsoft SharePoint Server 2019 (May 2026)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 16.0.5552.1002 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (314345). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.8
VulDB Temp Score: 7.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 8.8
Vendor Vector (Microsoft): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Unproven

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 314345
Nessus Name: Security Updates for Microsoft SharePoint Server 2019 (May 2026)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔒
0-Day Time: 🔒
Exposure Time: 🔒

Upgrade: SharePoint Server 16.0.5552.1002

Timelineinfo

05/12/2026 VulDB entry created
05/12/2026 +0 days Advisory disclosed
05/12/2026 +0 days Countermeasure disclosed
05/13/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-35439 (🔒)
GCVE (CVE): GCVE-0-2026-35439
GCVE (VulDB): GCVE-100-363169

Entryinfo

Created: 05/12/2026 19:34
Updated: 05/13/2026 08:33
Changes: 05/12/2026 19:34 (36), 05/12/2026 19:37 (34), 05/13/2026 08:33 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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