SB20260812230 - Multiple vulnerabilities in Microsoft SharePoint Server
Published: August 12, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Cross-site scripting (CVE-ID: CVE-2026-57105)
CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSSv4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
The vulnerability allows a remote user to perform spoofing.
The vulnerability exists due to cross-site scripting in Microsoft Office SharePoint when generating web pages. A remote user can send a malicious link to a user and convince the user to open it to perform spoofing.
User interaction is required to open a malicious link.
2) Deserialization of Untrusted Data (CVE-ID: CVE-2026-70321)
CWE-ID: CWE-502 - Deserialization of Untrusted Data
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to execute arbitrary code.
The vulnerability exists due to deserialization of untrusted data in Microsoft Office SharePoint when handling calls to arbitrary endpoints over a network. A remote user can call arbitrary endpoints to execute arbitrary code.
3) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2026-70324)
CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to elevate privileges.
The vulnerability exists due to server-side request forgery (ssrf) in Microsoft Office SharePoint when handling network requests. A remote user can send a specially crafted request to elevate privileges.
In some cases, exposed sensitive information could provide access to internal networks.
Remediation
Install update from vendor's website.