CVE-2021-3641

Improper Link Resolution Before File Access (Link Following) vulnerability in the EPAG component of Bitdefender Endpoint Security Tools for Windows allows a local attacker to cause a denial of service. This issue affects: Bitdefender GravityZone version 7.1.2.33 and prior versions.

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.bitdefender.com/support/security-advisories/improper-link-resolution-before-file-access-in-bitdefender-gravityzone-va-9921
• https://www.zerodayinitiative.com/advisories/ZDI-22-143/