The vulnerability arises from weak authentication logic in Microsoft SharePoint that allows an attacker without valid credentials to bypass a built‑in security feature. Classified as CWE‑1390, the flaw permits unauthorized access that could compromise confidentiality, integrity, or availability of data and services. By crafting authentication requests directed at the SharePoint server, the attacker can effectively elevate privileges during the initial login phase. The attack vector is inferred to be over the network, as the description explicitly states the bypass operates over a network connection, a deduction drawn from the provided text.

Affected products include Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, and the SharePoint Server Subscription Edition. No specific substratum versions are cited, so all current releases of these products remain susceptible to the vulnerability.

The CVSS score of 9.1 marks the flaw as high‑severity, and the EPSS score of 70% indicates a high probability of exploitation in the wild. The vulnerability is also listed in the CISA KEV catalog. No local user privileges are required; the attacker only needs network access to the vulnerable authentication endpoint and the ability to construct the malicious requests. Given the inferred network‑based attack vector, any SharePoint server exposed to the internet or an extensive corporate network faces significant risk of compromise.