Zero-day vulnerability in Atomymaxsite

Arbitrary file upload
CVE-2012-6498

The vulnerability was reported by ThaiCERT as a zero-day targeting websites across the country.

Vulnerability details

Advisory: SB2012101701 - Arbitrary file upload in Atomymaxsite

Vulnerable component: Atomymaxsite

CVE-ID: CVE-2012-6498

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C

CWE-ID: CWE-434 - Unrestricted Upload of File with Dangerous Type

Description:

The vulnerability allows a remote attacker to cause arbitrary code execution on the original server.

The weakness exists due to improper validation of file extensions in "index.php" script when uploading files. A remote attacker can upload arbitrary file with .php extension and execute it on the system with privileges of the web server.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Note: the vulnerability was being actively exploited.

External links:

https://www.thaicert.or.th/alerts/admin/2012/al2012ad025.html
http://www.websecuritywatch.com/atomymaxsite-2-5-unrestricted-file-upload-vulnerability/

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.