CVE-2019-3567

In some configurations an attacker can inject a new executable path into the extensions.load file for osquery and hard link a parent folder of a malicious binary to a folder with known safe permissions. Under those circumstances osquery will load said malicious executable with SYSTEM permissions. The solution is to migrate installations to the Program Files directory on Windows which restricts unprivileged write access. This issue affects osquery prior to v3.4.0.

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://www.facebook.com/security/advisories/cve-2019-3567