The file extension check in GNUBoard 3.40 and earlier only verifies extensions that contain all lowercase letters, which allows remote attackers to upload arbitrary files via file extensions that include uppercase letters.
                
                    Exploit prediction scoring system (EPSS) score
                    
                        
                            EPSS Score 0.018
                        
                    
                    
                        
                            EPSS Ranking 82.0%