[RESOLVED] Why does this search trigger XSS filter?

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barbaz
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[RESOLVED] Why does this search trigger XSS filter?

Post by barbaz »

Using the DuckDuckGo browser searchplugin (the xml file only, not the XPI they offer), searching for

Code: Select all

ksh add username to prompt
sets off the XSS filter. I haven't previously had XSS filter trouble with this searchplugin, and I don't think it auto-updates.
Why this particular search?
Console messages: (had to capture with a video capture program to view, so there may be typos, especially in that last set of numbers)

Code: Select all

[NoScript InjectionChecker]JavaScript Injection in ///?q=ksh+add+username+to+prompt
(function anonymous() {
q=ksh+add+username+to+prompt /* COMMENT_TERMINATOR */
DUMMY_EXPR
})

[NoScript XSS] Sanitized suspicious request.  Original URL [https://duckduckgo.com
/?q=ksh+add+username+to+prompt] requested from [chrome://navigator/content/navigator.xul].  Sanitized URL:
[https://duckduckgo.com/?q=ksh+add+userNAME+to+PROMPT#40824949409240163382].
*Always* check the changelogs BEFORE updating that important software!
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:32.0) Gecko/20100101 SeaMonkey/2.29.1
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Thrawn
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Re: Why does this search trigger XSS filter?

Post by Thrawn »

Have you whitelisted DuckDuckGo?

If not, then the XSS filter is very aggressive.
======
Thrawn
------------
Religion is not the opium of the masses. Daily life is the opium of the masses.

True religion, which dares to acknowledge death and challenge the way we live, is an attempt to wake up.
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barbaz
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Re: Why does this search trigger XSS filter?

Post by barbaz »

Yes, DDG is in my whitelist...
*Always* check the changelogs BEFORE updating that important software!
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:32.0) Gecko/20100101 SeaMonkey/2.29.1
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Thrawn
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Re: Why does this search trigger XSS filter?

Post by Thrawn »

Well, judging by what the filter did, it doesn't like 'name', which is frequently a JavaScript attribute, or 'prompt', which pops up an input box.

Does it still happen if you have another keyword after 'prompt'?
======
Thrawn
------------
Religion is not the opium of the masses. Daily life is the opium of the masses.

True religion, which dares to acknowledge death and challenge the way we live, is an attempt to wake up.
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:32.0) Gecko/20100101 Firefox/32.0
barbaz
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Posts: 11144
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Re: Why does this search trigger XSS filter?

Post by barbaz »

Thrawn wrote:Well, judging by what the filter did, it doesn't like 'name', which is frequently a JavaScript attribute, or 'prompt', which pops up an input box.
That kinda makes sense, but I didn't make "name" a completely separate word...
Thrawn wrote:Does it still happen if you have another keyword after 'prompt'?
Testing with the keyword "terminal", yes...
*Always* check the changelogs BEFORE updating that important software!
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:32.0) Gecko/20100101 SeaMonkey/2.29.1
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Giorgio Maone
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Re: Why does this search trigger XSS filter?

Post by Giorgio Maone »

It's a false negative from the new rules against exfiltration, which surely needs to be tweaked.
Checking it...
Mozilla/5.0 (Windows NT 6.3; WOW64; rv:32.0) Gecko/20100101 Firefox/32.0
barbaz
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Re: Why does this search trigger XSS filter?

Post by barbaz »

Fixed in 2.6.9rc2, thanks.
*Always* check the changelogs BEFORE updating that important software!
Mozilla/5.0 (X11; Linux i686; rv:32.0) Gecko/20140924 SeaMonkey/2.29.1pre
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