web commit by MichaelStevens: added new bug report

[git.ikiwiki.info.git] / doc / security.mdwn

diff --git a/doc/security.mdwn b/doc/security.mdwn
index 4db756e2e001fde219e2388586f9369cba45510e..01a893d2025c252526d7f449b0b7553578e5365c 100644 (file)
--- a/doc/security.mdwn
+++ b/doc/security.mdwn
@@ -6,6 +6,8 @@ security issues with this program than with cat(1). If, however, you let
 others edit pages in your wiki, then some possible security issues do need
 to be kept in mind.
 
 others edit pages in your wiki, then some possible security issues do need
 to be kept in mind.
 

+[[toc levels=2]]
+

 ----
 
 # Probable holes
 ----
 
 # Probable holes


@@ -16,15 +18,7 @@ _(The list of things to fix.)_
 
 Anyone with direct commit access can forge "web commit from foo" and
 make it appear on [[RecentChanges]] like foo committed. One way to avoid
 
 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.
-
-## XML::Parser
-
-XML::Parser is used by the aggregation plugin, and has some security holes
-that are still open in Debian unstable as of this writing. #378411 does not
-seem to affect our use, since the data is not encoded as utf-8 at that
-point. #378412 could affect us, although it doesn't seem very exploitable.
-It has a simple fix, which should be NMUed or something..
+this would be to limit web commits to those done by a certain user.

 
 ## other stuff to look at
 
 
 ## other stuff to look at
 


@@ -86,11 +80,15 @@ they can try to use this to exploit your web server.
 
 _(AKA, the assumptions that will be the root of most security holes...)_
 
 
 _(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.
 
 
 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
 ## publishing cgi scripts
 
 ikiwiki does not allow cgi scripts to be published as part of the wiki. Or


@@ -138,7 +136,9 @@ file not be world readable.
 
 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.
 
 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
 
 
 ## XSS holes in CGI output
 


@@ -149,6 +149,27 @@ with a username containing html code (anymore).
 It's difficult to know for sure if all such avenues have really been
 closed though.
 
 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
 ----
 
 # Fixed holes


@@ -242,3 +263,33 @@ have come just before yours, by forging svn log output. This was
 guarded against by using svn log --xml.
 
 ikiwiki escapes any html in svn commit logs to prevent other mischief.
 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.