CVE-2023-0652

Due to a hardlink created in the ProgramData folder during the repair process of the software, the installer (MSI) of WARP Client for Windows (<= 2022.12.582.0) allowed a malicious attacker to forge the destination of the hardlink and escalate privileges, overwriting SYSTEM protected files. As Cloudflare WARP client for Windows (up to version 2022.5.309.0) allowed creation of mount points from its ProgramData folder, during installation of the WARP client, it was possible to escalate privileges and overwrite SYSTEM protected files.

Weakness

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.

Affected Software

Potential Mitigations

• Follow the principle of least privilege when assigning access rights to entities in a software system.
• Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/132.html
• https://cwe.mitre.org/data/definitions/17.html
• https://cwe.mitre.org/data/definitions/35.html
• https://cwe.mitre.org/data/definitions/76.html

References

• https://developers.cloudflare.com/warp-client/get-started/windows/
• https://github.com/cloudflare/advisories/security/advisories/GHSA-xmhj-9p83-xvw9
• https://install.appcenter.ms/orgs/cloudflare/apps/1.1.1.1-windows-1/distribution_groups/release