CVE-2026-54108: Microsoft SharePoint Server Spoofing Vulnerability

mediumCVSS 6.5CVE-2026-54108

External control of file name or path in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.

CSIRTS triage

vendor: Microsoft product: SharePoint ServerOther

What: External control of file name or path in Microsoft Office SharePoint allows an authorized attacker to perform spoofing over a network.
Who is affected: Users of Microsoft SharePoint Server.
Urgency: Remediation is medium urgency due to the potential for network spoofing.
Action: Apply the latest updates for Microsoft SharePoint Server.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 6.5
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-54108

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-541080.78% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 52% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-54108	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownexploitedNCSC-2026-0237 [1.02] [H/H] Vulnerabilities Fixed in Microsoft Officencsc-nl
unknownexploitedNCSC-2026-0237 [1.01] [H/H] Vulnerabilities fixed in Microsoft Officencsc-nl
unknownexploitedNCSC-2026-0237 [1.00] [M/H] Vulnerabilities fixed in Microsoft Officencsc-nl
mediumCVE-2026-54108: External control of file name or path in Microsoft Office SharePoint allows an authorized atta…nvd

Recent advisories for Microsoft SharePoint Server

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

medium[NEW] [medium] Microsoft SharePoint and SharePoint Server: Vulnerability allows Cross-Site Scriptingcert-bund · 2026-07-17
criticalexploitedAL26-017 - Critical vulnerabilities impacting Microsoft SharePoint Server – CVE-2026-56164, CVE-2026-55040 and…cccs · 2026-07-15
mediumCVE-2026-55051: Server-side request forgery (ssrf) in Microsoft Office SharePoint allows an authorized attacke…nvd · 2026-07-14
mediumCVE-2026-55135: Microsoft SharePoint Server Spoofing Vulnerabilitymsrc · 2026-07-14
highCVE-2026-55126: Microsoft SharePoint Server Spoofing Vulnerabilitymsrc · 2026-07-14
mediumCVE-2026-55020: Microsoft SharePoint Server Spoofing Vulnerabilitymsrc · 2026-07-14