Seeyon A6 collaborative office automation platform contains an unauthenticated SQL injection vulnerability in the attachids parameter of the file attachment download endpoint that allows remote attackers to extract arbitrary database contents without prior authentication. Attackers can inject UNION-based SQL statements through the attachids request parameter in downloadAtt.jsp to retrieve sensitive information including credentials and system configuration data. Exploitation evidence was first observed by the Shadowserver Foundation on 2023-10-17.