Microsoft Outlook Information Disclosure Vulnerability

Security Vulnerability

Released: Nov 13, 2018

Assigning CNA
Microsoft
CVE.org link
CVE-2018-8558
Impact
Information Disclosure
Max Severity
Important

Executive Summary

An information disclosure vulnerability exists when Microsoft Outlook fails to respect "Default link type" settings configured via the SharePoint Online Admin Center.

A malicious user could potentially share anonymously-accessible links to other users via email where these links are intended to be accessed only by specific users.

The security update addresses the vulnerability by correcting how Microsoft Outlook generates links inserted into emails via the "Attach File" interface.

Exploitability

The following table provides an exploitability assessment for this vulnerability at the time of original publication.

Publicly disclosed
No
Exploited
No
Exploitability assessment
Exploitation Less Likely

FAQ

What type of information could be disclosed by this vulnerability?

The type of information that could be disclosed if an attacker successfully exploited this vulnerability is unauthorized file system access - reading from the file system.

Acknowledgements

Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgements for more information.

Security Updates

To determine the support lifecycle for your software, see the Microsoft Support Lifecycle.

Release date Descending

Disclaimer

The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

Revisions

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