samples of vulnerability in code

 （1）system(fileCmd);处存在命令执行漏洞及任意文件删除问题，需要进行命令执行过滤. Arbitrary command execution.

（2）printf(fileCmd);处存在格式化字符串漏洞，此处可以通过%s来打印命令. Format string attack.

（3）fileContent =readBase64File(filePath);处存在目录穿越，任意文件读取漏洞，此处可以对../这种目录穿越特征进行过滤. 

（4）strcpy(filePath, dirPaths[dirIdx]);处存在数组访问越界，从而可以也可以导致缓冲区溢出问题，判断有符号数的dirIdx时需要判断其大于等于0. bufferoverflow




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