CVE-2021-26089

An improper symlink following in FortiClient for Mac 6.4.3 and below may allow an non-privileged user to execute arbitrary privileged shell commands during installation phase.

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://fortiguard.com/advisory/FG-IR-21-022
• https://www.zerodayinitiative.com/advisories/ZDI-22-078/