CRITICAL CISA KEV

CVE-2026-58644

CVSS v3

9.8

CRITICAL

EPSS Score

1.3%

exploit probability

CISA KEV

Yes

known exploited

Exploitation

SSVC status

Description

Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.

CISA Known Exploited Vulnerability

Date Added
7/16/2026
Patch Due Date
7/19/2026
Ransomware Use
Unknown

Technical details

CVSS v3 Vector
3.1
Published
7/14/2026
Last Modified
7/15/2026

Frequently asked questions

What is CVE-2026-58644?

Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.

Is CVE-2026-58644 actively exploited?

Yes. CVE-2026-58644 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 7/19/2026.

What is the CVSS score for CVE-2026-58644?

CVE-2026-58644 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string 3.1.

Is CVE-2026-58644 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.