SynopsisThe Microsoft SharePoint Server installation on the remote host is affected by multiple vulnerabilities.
DescriptionThe Microsoft SharePoint Server installation on the remote host is missing security updates. It is, therefore, affected by multiple vulnerabilities :
- An authentication bypass vulnerability exists in Windows Communication Foundation (WCF) and Windows Identity Foundation (WIF), allowing signing of SAML tokens with arbitrary symmetric keys. This vulnerability allows an attacker to impersonate another user, which can lead to elevation of privileges. The vulnerability exists in WCF, WIF 3.5 and above in .NET Framework, WIF 1.0 component in Windows, WIF Nuget package, and WIF implementation in SharePoint. An unauthenticated attacker can exploit this by signing a SAML token with any arbitrary symmetric key. This security update addresses the issue by ensuring all versions of WCF and WIF validate the key used to sign SAML tokens correctly.
- A cross-site-scripting (XSS) vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server. An authenticated attacker could exploit the vulnerability by sending a specially crafted request to an affected SharePoint server. The attacker who successfully exploited the vulnerability could then perform cross-site scripting attacks on affected systems and run script in the security context of the current user. The attacks could allow the attacker to read content that the attacker is not authorized to read, use the victim's identity to take actions on the SharePoint site on behalf of the user, such as change permissions and delete content, and inject malicious content in the browser of the user. The security update addresses the vulnerability by helping to ensure that SharePoint Server properly sanitizes web requests. (CVE-2019-1134)
SolutionMicrosoft has released the following security updates to address this issue: