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From Jim Manico <>
Subject Re: Cookies are broken in 6.0.16?
Date Sat, 09 Feb 2008 22:33:24 GMT
 >   response.addCookie(new Cookie("test_cookie3", "123===")) looks like 
something which should be working.

Honestly, this is not user driven - it's only server programmer driven. 
I would dare to say this is either absolutely horrible server side 
programming or a possible attempt at a hack/attack and drop the request 
altogether. If you really need an equals sign in your cookie data, then 
you must URL Encode it. If multiple equal signs appear unencodede, then 
it's malformed and should be rejected outright.

- Jim

> On Sat, 2008-02-09 at 13:03 +0000, Mark Thomas wrote:
>> Maik Jablonski wrote:
>>> Hi,
>>> I've just encountered that Cookies seem to be a little bit broken in
>>> 6.0.16. If you want to read a cookie which ends on one or more
>>> equals-sign (=), the equals-signs are removed by Tomcat when the
>>> cookie is read.
>>> Is it a bug or a "undocumented" change?
>> It is neither. The changes are documented in the change log. As a result of
>> a couple of minor security issues (see
>> the cookie handling code has been
>> tightened up to make it spec compliant.
>> By default the servlet spec uses version 0 cookies. The name value pairs
>> are defined as:
>> <spec-quote>
>> This string is a sequence of characters excluding semi-colon, comma and
>> white space. If there is a need to place such data in the name or value,
>> some encoding method such as URL style %XX encoding is recommended, though
>> no encoding is defined or required.
>> </spec-quote>
>> The difficulty here is that although '=' is the delimiter between NAME and
>> VALUE there is no need to encode it if it appears in the name or the value.
>> This causes some ambiguities when parsing a header of the form:
>> Set-Cookie: foo=bar=bartoo
>> Is the name 'foo' or 'foo=bar'? Is the value 'bar=bartoo' or 'bartoo'?
>> The changes to the cookie parsing mean the second '=' and any text beyond
>> it are now ignored.
>> If you set the cookie version to 1 then the quoting will be applied where
>> necessary and your example will work as you intend.
> It seems to me like an annoying regression. response.addCookie(new
> Cookie("test_cookie3", "123===")) looks like something which should be
> working. Are you sure there's nothing that could be done about it ?
> Maybe some additional encoding for '=' when not quoting ?
> Rémy
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