Cyber Resilience

CVE-2026-55051

SSRF in Microsoft Sharepoint Server ≤ 16.0.19725.20434

SSRF
Published
14 July 2026
Modified
16 July 2026
Patch / advisory
View advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0058 44th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-55051 is a medium-severity SSRF (CWE-918) vulnerability in Microsoft Sharepoint Server. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 44th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-4 (Information Flow Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability Data

Server-side request forgery (ssrf) in Microsoft Office SharePoint allows an authorized attacker to disclose information over a network.

CWE(s)
CWE-918

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Why these techniques?

SSRF vulnerability in public-facing SharePoint directly enables exploitation of the application to disclose internal information.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2024-32987Same product: Microsoft Sharepoint Server
CVE-2026-20958Same product: Microsoft Sharepoint Server
CVE-2025-53760Same product: Microsoft Sharepoint Server
CVE-2025-64663Same vendor: Microsoft
CVE-2023-33159Same product: Microsoft Sharepoint Server
CVE-2023-36764Same product: Microsoft Sharepoint Server
CVE-2023-36892Same product: Microsoft Sharepoint Server
CVE-2023-33157Same product: Microsoft Sharepoint Server
CVE-2023-36891Same product: Microsoft Sharepoint Server
CVE-2023-36890Same product: Microsoft Sharepoint Server

Affected Assets

microsoft
sharepoint server
2016, 2019 · ≤ 16.0.19725.20434

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-4 Information Flow Enforcement
  • SI-10 Information Input Validation
  • SC-7 Boundary Protection
Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.3.6
  • V1.5.3
  • V5.3.2
  • V10.4.7

Mitigating Controls (NIST 800-53 r5) AI

AC-4 Information Flow Enforcement good match
prevent

Enforces information flow policies to block the server from initiating unauthorized outbound requests to internal resources via SSRF.

SI-10 Information Input Validation good match
prevent

Validates all URL and request inputs to reject malicious external or internal targets that enable SSRF information disclosure.

SC-7 Boundary Protection partial match
prevent

Restricts outbound network connections from the SharePoint server, limiting the destinations reachable through an SSRF exploit.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure development practices directly include input validation and destination allow-listing that prevent SSRF.

DE.CM-09 partial match
prevents

Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover and record SSRF flaws in web applications.

PR.IR-01 partial match
prevents

Network segmentation and egress controls can limit the damage from successful SSRF requests.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.7 Threat intelligence partial match
prevents

Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.

References