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CVE-2018-8955: Bitdefender Gravityzone: Remote code execution

CVE-2018-8955 is rated critical with a CVSS v3.0 base score of 9.8 and affects Bitdefender Gravityzone. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

The installer for BitDefender GravityZone relies on an encoded string in a filename to determine the URL for installation metadata, which allows remote attackers to execute arbitrary code by changing the filename while leaving the file's digital signature unchanged.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Unchanged. Impact stays within the vulnerable component.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
• Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-347: Improper Verification of Cryptographic Signature

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

Affected products

• Bitdefender Gravityzone: all versions listed by NVD

References

• http://packetstormsecurity.com/files/149900/Bitdefender-GravityZone-Installer-Signature-Bypass-Code-Execution.html
• http://seclists.org/fulldisclosure/2018/Oct/44
• http://www.securitytracker.com/id/1041940
• https://labs.nettitude.com/blog/cve-2018-8955-bitdefender-gravityzone-arbitrary-code-execution/