web commit by JoshTriplett: Copyedit.

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

diff --git a/doc/security.mdwn b/doc/security.mdwn
index b294decc818006b55b71f1dcc8b9b54c35159ecb..72ae8f4b90a88dfe160261b56010ae46c6cb5a1f 100644 (file)
--- a/doc/security.mdwn
+++ b/doc/security.mdwn
@@ -1,4 +1,4 @@
-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
 
 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


@@ -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


@@ -16,12 +18,12 @@ _(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.
+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
 
 ## 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.

 
 ----
 
 
 ----
 


@@ -41,7 +43,7 @@ Of course nobody else seems to worry about this in other wikis, so should we?
 
 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).
 
 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.
 
 doesn't support file uploads from browsers (yet), so they can't exploit
 this.
 


@@ -78,11 +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


@@ -130,7 +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
 


@@ -141,6 +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


@@ -234,3 +263,19 @@ 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.