Horizon Alert
Summary of the vulnerability and why it matters
Microsoft SharePoint has an authentication flaw that permits an unauthorized attacker to impersonate legitimate users over a network. This vulnerability could enable an attacker to gain access to sensitive information or alter disclosed data. The core issue lies in how the system verifies user identities, allowing for improper authentication.
- SharePoint Server, Enterprise Server
- Flaw in identity verification process
- Unauthorized information access and modification
Attack Path
How an attacker could exploit the issue
An attacker can leverage an improper authentication vulnerability in Microsoft Office SharePoint to impersonate an authorized user over a network. This could lead to the unauthorized disclosure and modification of sensitive information. The exploitation is facilitated by the presence of vulnerable SharePoint instances exposed to the network, requiring no specific privileges to initiate the attack.
- Exposed SharePoint instances.
- Attacker initiates network connection.
- User data is viewed or modified.
Live Threat
Current exploitation, exposure, and threat context
A vulnerability in Microsoft SharePoint's authentication processes could allow unauthorized individuals to impersonate legitimate users over a network. This could lead to the unauthorized disclosure of sensitive information and potentially allow for modifications to that information. The risk is amplified as this vulnerability has been observed in active exploitation and is listed on a known exploited vulnerabilities catalog.
- Likely attacker skill: Low
- Required access: Network access
- Business risk: High, urgent action required
Priority actions
Operational Fix
Recommended remediation, mitigation, and detection steps
Microsoft SharePoint contains an improper authentication vulnerability that permits unauthorized network spoofing, potentially exposing sensitive data. This issue is actively exploited in the wild. Affected organizations should prioritize immediate actions to protect their environments.
- Identify all exposed SharePoint assets.
- Reduce exposure or isolate risk.
- Apply vendor fixes, verify, and monitor.
