CVE-2005-3909 in Post Affiliate Pro
Summary
by MITRE
SQL injection vulnerability in merchants/index.php in Post Affiliate Pro 2.0.4 and earlier allows remote attackers to execute arbitrary SQL commands via the sortorder parameter.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/27/2025
The vulnerability identified as CVE-2005-3909 represents a critical sql injection flaw within the Post Affiliate Pro affiliate marketing software version 2.0.4 and earlier. This vulnerability exists in the merchants/index.php script where user input is not properly sanitized before being incorporated into sql queries. The specific parameter affected is sortorder which is used to determine the ordering of merchant listings in the administrative interface. Attackers can exploit this weakness by crafting malicious input through the sortorder parameter that gets directly embedded into database queries without adequate validation or escaping mechanisms.
This sql injection vulnerability falls under the common weakness enumeration CWE-89 which specifically addresses sql injection vulnerabilities where untrusted data is incorporated into sql commands without proper sanitization. The attack vector is particularly concerning as it allows remote attackers to execute arbitrary sql commands against the underlying database system. The vulnerability demonstrates a classic lack of input validation and output encoding that violates fundamental security principles for preventing injection attacks. The impact extends beyond simple data theft as attackers can potentially gain complete control over the database, modify affiliate records, manipulate commission calculations, or even escalate privileges within the application.
The operational impact of this vulnerability is severe for organizations using Post Affiliate Pro 2.0.4 or earlier versions as it provides attackers with unrestricted access to sensitive affiliate marketing data. Database compromise could result in unauthorized modification of affiliate commission structures, manipulation of merchant relationships, and potential exposure of confidential financial information. The vulnerability also aligns with ATT&CK technique T1071.004 which covers application layer protocol manipulation, specifically targeting web application interfaces. Organizations may face significant business disruption including loss of trust from partners, regulatory compliance violations, and potential legal consequences from data breaches. The remote nature of the attack means that exploitation can occur from anywhere on the internet without requiring physical access to the system or knowledge of internal network structures.
Mitigation strategies for this vulnerability should prioritize immediate patching of the Post Affiliate Pro software to version 2.0.5 or later where the sql injection flaw has been addressed. Organizations should implement proper input validation and output encoding mechanisms to sanitize all user-supplied data before processing. The principle of least privilege should be applied to database accounts used by the application, ensuring that database connections have minimal required permissions. Additionally, implementing web application firewalls and intrusion detection systems can help identify and block malicious sql injection attempts. Regular security assessments and code reviews should be conducted to identify similar vulnerabilities in other application components, while maintaining up-to-date security monitoring to detect potential exploitation attempts. The vulnerability serves as a reminder of the critical importance of proper input validation and the necessity of keeping software components updated to protect against known security flaws.