This security restriction is to avoid cross-site scripting attacks (XSS).

这个安全限制是为了避免跨站点脚本攻击(XSS)。

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This script is vulnerable to cross-site scripting attacks because it blindly prints out submitted form data.

该脚本容易受跨站点脚本攻击，因为它盲目输出所提交的表单数据。

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Cross-site scripting attacks pose an immense risk.

跨站点脚本攻击带来了巨大的风险。

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But cross-site scripting, a bug that allows a user to be tricked into clicking on a maliciously-crafted URL that causes a site to run a potentially dangerous script in their browser, still affects more than half of sites it tested.

FORBES: Researchers Say The Web May Be Offering Fewer Footholds To Hackers

In fact, cross-site scripting may be the most common unpatched bug in the world.

FORBES: Magazine Article

Many of those gadgets, Sutton has discovered, are vulnerable to "cross-site scripting, " a technique that could allow a hacker to impersonate a legitimate user.

FORBES: Magazine Article