encodeForHTMLAttribute vs encodeForJavaScript

时间:2017-07-10 02:21:38

标签: javascript security escaping xss esapi

我试图找出encodeForHTMLAttributeencodeForJavaScript之间的区别。尽管如此,我还是找不到将不受信任的数据用作javascript数据值的情况,这些数据值在使用encodeForHTMLAttribute进行转义时会破坏代码,但在使用encodeForJavaScript进行转义后可以安全地运行。

我知道对于所有javascript,建议使用encodeForJavaScript。但我喜欢看到差异。

1 个答案:

答案 0 :(得分:1)

你的问题的答案很无聊:事实是将HTML实体编码的字符串传递给JavaScript在很大程度上是一个未指定的操作。* JavaScript期望传递给它的数据被转义为JavaScript,但某些API方法除外,它不知道你发送了什么。

HTMLJavaScript是不同的语言。如果你注意的话,它们都有不同的保留字符 - 有些相同,这意味着它们每个都有保留字符组成了在使用那种语言时必须特别对待的语言。 < / p>

确保javascript 总是将传入代码视为数据的正确方法是为JavaScript转义。传递一个HTMLEntity编码的字符串,可能工作,但我们必须说可能因为该行为未指定。我在开始时链接的问题部分回答你的问题的一个原因是,JavaScript框架通常对你的输入进行那种处理......所以你最好确保如果发生这种情况,数据会被适当地转义为JavaScript的。否则它将解包你的HTMLEntity编码,渲染和执行脚本代码。

我将该死的部分保存到最后:You can write legal JavaScript with only six characters.这些字符的 none 通常由HTML编码器转义。 Here's an entire guide on using JavaScript escaping like this to evade XSS filters.要证明其有效,请查看here.

或者在计算机上的HTML文件中自行运行:

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但是,如果你逃避Javascript的<script>标签之间的内容......它将被视为纯粹的数据并且不会被执行。

*除了那些旨在将HTML编码的字符串作为输入的JavaScript函数。