The vulnerability is an improper input validation flaw in Microsoft SharePoint Server that allows an authorized attacker to perform spoofing over a network. By providing crafted input that is not properly sanitized, the attacker can cause the server to accept or render content that appears to originate from a trusted source.

Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, and Microsoft SharePoint Server Subscription Edition are affected. No specific sub‑release or patch level is cited, until updated.

The CVSS score of 4.6 indicates a moderate impact. The EPSS score of <1% suggests a very low probability of exploitation. The vulnerability is not listed in the CISA KEV catalog. The likely attack vector inferred from the description is an authenticated user with permission to submit content. Once exploiting the flaw, the attacker can cause SharePoint to display content that falsely appears to come from a trusted source. No publicly exposed unauthenticated path is required to exploit the vulnerability.