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IIUC, the current version of [HTML::Scrubber][] allows for the `object` tags to be either enabled or disabled entirely. However, while `object` can be used to add *code* (which is indeed a potential security hole) to a document, reading [Objects, Images, and Applets in HTML documents][objects-html] reveals that the “dangerous” are not all the `object`s, but rather those having the following attributes:
classid %URI; #IMPLIED -- identifies an implementation --
codebase %URI; #IMPLIED -- base URI for classid, data, archive--
codetype %ContentType; #IMPLIED -- content type for code --
archive CDATA #IMPLIED -- space-separated list of URIs --
It seems that the following attributes are, OTOH, safe:
declare (declare) #IMPLIED -- declare but don't instantiate flag --
data %URI; #IMPLIED -- reference to object's data --
type %ContentType; #IMPLIED -- content type for data --
standby %Text; #IMPLIED -- message to show while loading --
height %Length; #IMPLIED -- override height --
width %Length; #IMPLIED -- override width --
usemap %URI; #IMPLIED -- use client-side image map --
name CDATA #IMPLIED -- submit as part of form --
tabindex NUMBER #IMPLIED -- position in tabbing order --
Should the former attributes be *scrubbed* while the latter left intact, the use of the `object` tag would seemingly become safe.
Note also that allowing `object` (either restricted in such a way or not) automatically solves the [[/todo/svg]] issue.
For Ikiwiki, it may be nice to be able to restrict [URI's][URI] (as required by the `data` and `usemap` attributes) to, say, relative and `data:` (as per [RFC 2397][]) ones as well, though it requires some more consideration.
— [[Ivan_Shmakov]], 2010-03-12Z.
[[wishlist]]
## See also
* [Objects, Images, and Applets in HTML documents][objects-html]
* [[plugins/htmlscrubber|/plugins/htmlscrubber]]
* [[todo/svg|/todo/svg]]
* [RFC 2397: The “data” URL scheme. L. Masinter. August 1998.][RFC 2397]
* [Uniform Resource Identifier — the free encyclopedia][URI]
[HTML::Scrubber]: http://search.cpan.org/~podmaster/HTML-Scrubber-0.08/Scrubber.pm
[objects-html]: http://www.w3.org/TR/1999/REC-html401-19991224/struct/objects.html
[RFC 2397]: http://tools.ietf.org/html/rfc2397
[URI]: http://en.wikipedia.org/wiki/Uniform_Resource_Identifier
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