-Let's do an ikiwiki security analysis..
+Let's do an ikiwiki security analysis.
If you are using ikiwiki to render pages that only you can edit, do not
generate any wrappers, and do not use the cgi, then there are no more
others edit pages in your wiki, then some possible security issues do need
to be kept in mind.
+[[toc levels=2]]
+
----
# Probable holes
Anyone with direct commit access can forge "web commit from foo" and
make it appear on [[RecentChanges]] like foo committed. One way to avoid
-this would be to limit web commits to those done by a certian user.
+this would be to limit web commits to those done by a certain user.
## other stuff to look at
I need to audit the git backend a bit, and have been meaning to
-see if any CRLF injection type things can be done.
+see if any CRLF injection type things can be done in the CGI code.
----
Currently only people with direct svn commit access can upload such files
(and if you wanted to you could block that with a svn pre-commit hook).
-Wsers with only web commit access are limited to editing pages as ikiwiki
+Users with only web commit access are limited to editing pages as ikiwiki
doesn't support file uploads from browsers (yet), so they can't exploit
this.
_(AKA, the assumptions that will be the root of most security holes...)_
-## exploting ikiwiki with bad content
+## exploiting ikiwiki with bad content
Someone could add bad content to the wiki and hope to exploit ikiwiki.
Note that ikiwiki runs with perl taint checks on, so this is unlikely.
+One fun thing in ikiwiki is its handling of a PageSpec, which involves
+translating it into perl and running the perl. Of course, this is done
+*very* carefully to guard against injecting arbitrary perl code.
+
## publishing cgi scripts
ikiwiki does not allow cgi scripts to be published as part of the wiki. Or
Login to the wiki involves sending a password in cleartext over the net.
Cracking the password only allows editing the wiki as that user though.
-If you care, you can use https, I suppose.
+If you care, you can use https, I suppose. If you do use https either for
+all of the wiki, or just the cgi access, then consider using the sslcookie
+option.
## XSS holes in CGI output
It's difficult to know for sure if all such avenues have really been
closed though.
+## HTML::Template security
+
+If the [[plugins/template]] plugin is enabled, users can modify templates
+like any other part of the wiki. This assumes that HTML::Template is secure
+when used with untrusted/malicious templates. (Note that includes are not
+allowed, so that's not a problem.)
+
+----
+
+# Plugins
+
+The security of [[plugins]] depends on how well they're written and what
+external tools they use. The plugins included in ikiwiki are all held to
+the same standards as the rest of ikiwiki, but with that said, here are
+some security notes for them.
+
+* The [[plugins/img]] plugin assumes that imagemagick/perlmagick are secure
+ from malformed image attacks. Imagemagick has had security holes in the
+ past. To be able to exploit such a hole, a user would need to be able to
+ upload images to the wiki.
+
----
# Fixed holes
guarded against by using svn log --xml.
ikiwiki escapes any html in svn commit logs to prevent other mischief.
+
+## XML::Parser
+
+XML::Parser is used by the aggregation plugin, and has some security holes.
+Bug #[378411](http://bugs.debian.org/378411) does not
+seem to affect our use, since the data is not encoded as utf-8 at that
+point. #[378412](http://bugs.debian.org/378412) could affect us, although it
+doesn't seem very exploitable. It has a simple fix, and has been fixed in
+Debian unstable.
+
+## include loops
+
+Various directives that cause one page to be included into another could
+be exploited to DOS the wiki, by causing a loop. Ikiwiki has always guarded
+against this one way or another; the current solution should detect all
+types of loops involving preprocessor directives.
+
+## Online editing of existing css and images
+
+A bug in ikiwiki allowed the web-based editor to edit any file that was in
+the wiki, not just files that are page sources. So an attacker (or a
+genuinely helpful user, which is how the hole came to light) could edit
+files like style.css. It is also theoretically possible that an attacker
+could have used this hole to edit images or other files in the wiki, with
+some difficulty, since all editing would happen in a textarea.
+
+This hole was discovered on 10 Feb 2007 and fixed the same day with the
+release of ikiwiki 1.42. A fix was also backported to Debian etch, as
+version 1.33.1. I recommend upgrading to one of these versions if your wiki
+allows web editing.
+
+## html insertion via title
+
+Missing html escaping of the title contents allowed a web-based editor to
+insert arbitrary html inside the title tag of a page. Since that part of
+the page is not processed by the htmlscrubber, evil html could be injected.
+
+This hole was discovered on 21 March 2007 and fixed the same day (er, hour)
+with the release of ikiwiki 1.46. A fix was also backported to Debian etch,
+as version 1.33.2. I recommend upgrading to one of these versions if your
+wiki allows web editing or aggregates feeds.
+
+## javascript insertion via meta tags
+
+It was possible to use the meta plugin's meta tags to insert arbitrary
+url contents, which could be used to insert stylesheet information
+containing javascript. This was fixed by sanitising meta tags.
+
+This hole was discovered on 21 March 2007 and fixed the same day
+with the release of ikiwiki 1.47. A fix was also backported to Debian etch,
+as version 1.33.3. I recommend upgrading to one of these versions if your
+wiki can be edited by third parties.