Microsoft OneDrive on Windows link following

Summaryinfo

A vulnerability was found in Microsoft OneDrive on Windows and classified as critical. The impacted element is an unknown function. Executing a manipulation can lead to link following. This vulnerability appears as CVE-2020-16851. The attack may be performed from remote. There is no available exploit. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as critical was found in Microsoft OneDrive on Windows (Cloud Software) (the affected version is unknown). This vulnerability affects an unknown code. The manipulation with an unknown input leads to a link following vulnerability. The CWE definition for the vulnerability is CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

<p>An elevation of privilege vulnerability exists when the OneDrive for Windows Desktop application improperly handles symbolic links. An attacker who successfully exploited this vulnerability could overwrite a targeted file with an elevated status.</p> <p>To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and delete a targeted file with an elevated status.</p> <p>The update addresses this vulnerability by correcting where the OneDrive updater performs file writes while running with elevation.</p>

The weakness was presented 09/08/2020 as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. The public release was coordinated in cooperation with the vendor. This vulnerability was named CVE-2020-16851. The attack can be initiated remotely. A single authentication is needed for exploitation. There are neither technical details nor an exploit publicly available. The advisory points out:

An elevation of privilege vulnerability exists when the OneDrive for Windows Desktop application improperly handles symbolic links. An attacker who successfully exploited this vulnerability could overwrite a targeted file with an elevated status.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

See VDB-160950 and VDB-160949 for similar entries. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Cloud Software

Vendor

• Microsoft

Name

• OneDrive

License

• commercial

Website

• Vendor: https://www.microsoft.com/

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Once again VulDB remains the best source for vulnerability data.

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