How severe is CVE-2026-45484?

CVE-2026-45484 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-45484 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45484?

CVE-2026-45484 primarily affects Microsoft Sharepoint Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-45484?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-45484 have an EU (EUVD) identifier?

Yes. CVE-2026-45484 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35581.

When was CVE-2026-45484 published?

CVE-2026-45484 was published on 2026-06-09 and last updated on 2026-06-17.

CVE-2026-45484

CVE-2026-45484 is a high-severity vulnerability in Microsoft Sharepoint Server with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35581
Weakness: CWE-502
Affected product: Microsoft Sharepoint Server
Published: 2026-06-09
Last modified: 2026-06-17

Description

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.

Frequently asked questions

What is CVE-2026-45484?: Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to elevate privileges over a network.
How severe is CVE-2026-45484?: CVE-2026-45484 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-45484 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45484?: CVE-2026-45484 primarily affects Microsoft Sharepoint Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-45484?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-45484 have an EU (EUVD) identifier?: Yes. CVE-2026-45484 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35581.
When was CVE-2026-45484 published?: CVE-2026-45484 was published on 2026-06-09 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45484

Affected products (3)

cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*

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