Vulnerability · CVE-2026-50522
Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
Published Jul 14, 2026 · catalog updated Jul 23, 2026 · Microsoft SharePoint
Patch now
CVE-2026-50522 is in the CISA known-exploited catalog, due Jul 25, 2026. Confirm Microsoft SharePoint against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- Critical9.8
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 3.04%
- Remediation
- Remediation guidance
- Affected products
- cpe microsoft/sharepoint server · vendor Microsoft SharePoint
Microsoft SharePoint contains a deserialization of untrusted data vulnerability which could allow an unauthorized attacker to execute code over a network. Initial-access exploit intelligence.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe microsoft/sharepoint server2016
- cpe microsoft/sharepoint server2019
- vendor Microsoft SharePointversion unspecified
How to fix CVE-2026-50522
Recommended remediation
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. CISA due date Jul 25, 2026.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2026-50522 is in the CISA known-exploited catalog, due Jul 25, 2026. Confirm Microsoft SharePoint against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Compare what you have installed with microsoft/sharepoint server 2016; microsoft/sharepoint server 2019. Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
What should an analyst verify?
CWE-502: Deserialization of Untrusted Data. EPSS 3.04%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Jul 14, 2026 · Catalog
Detected
Microsoft SharePoint contains a deserialization of untrusted data vulnerability which could allow an unauthorized attacker to execute code over a network.
Jul 22, 2026 · CISA KEV
Known exploited
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating
Jul 23, 2026 · Catalog
Updated
Microsoft SharePoint contains a deserialization of untrusted data vulnerability which could allow an unauthorized attacker to execute code over a network.
Jul 25, 2026 · CISA KEV
Remediation due
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating
Sources
- CISA KEVConfirmed exploitationCVE-2026-50522
Microsoft SharePoint contains a deserialization of untrusted data vulnerability which could allow an unauthorized attacker to execute code over a network.
cisa.gov - CVE.orgVulnerability recordCVE-2026-50522
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-50522
30-day exploitation probability 3.0%
first.org - JPCERT/CCGovernment advisoryCVE-2026-50522
[Updated] Microsoft Releases July 2026 Security Updates
jpcert.or.jp - NIST NVDVulnerability recordCVE-2026-50522
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2026-50522
Microsoft SharePoint contains a deserialization of untrusted data vulnerability which could allow an unauthorized attacker to execute code over a network.
vulncheck.com
References
- VulnCheck exploitation evidence · blog.hunterstrategy.net
- CISA note · msrc.microsoft.com
- CISA note · nvd.nist.gov
- VulnCheck exploitation evidence · previdian.com
- US Government Resource · cisa.gov
- CISA note · cisa.gov
- CISA note · cisa.gov
- VulnCheck exploitation evidence · cisa.gov
- VulnCheck exploitation evidence · linkedin.com
- VulnCheck exploitation evidence · recordedfuture.com
- VulnCheck exploitation evidence · x.com
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.