some updates about the recent hole

[ikiwiki.git] / doc / security.mdwn

diff --git a/doc/security.mdwn b/doc/security.mdwn
index 6e1d56a52e76c92a50a6a48d66293f5b3a3022d4..9259209eeb34e99714d247dfee1144e929c90533 100644 (file)
--- a/doc/security.mdwn
+++ b/doc/security.mdwn
@@ -47,6 +47,13 @@ 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.
 
+It is possible to embed an image in a page edited over the web, by using
+`img src="data:image/png;"`. Ikiwiki's htmlscrubber only allows `data:`
+urls to be used for `image/*` mime types. It's possible that some broken
+browser might ignore the mime type and if the data provided is not an
+image, instead run it as javascript, or something evil like that. Hopefully
+not many browsers are that broken.
+
 ## multiple accessors of wiki directory
 
 If multiple people can directly write to the source directory ikiwiki is
@@ -341,7 +348,20 @@ There are at least two configurations where this is exploitable:
   notice.
 
 This security hole was discovered on 26 November 2007 and fixed the same
-da with the release of ikiwiki 2.14. I recommend upgrading to this version
+day with the release of ikiwiki 2.14. I recommend upgrading to this version
 if your wiki can be committed to by third parties. Alternatively, don't use
 a trailing slash in the srcdir, and avoid the (unusual) configurations that
 allow the security hole to be exploited.
+
+## javascript insertion via uris
+
+The htmlscrubber did not block javascript in uris. This was fixed by adding
+a whitelist of valid uri types, which does not include javascript. Some
+urls specifyable by the meta plugin could also theoretically have been used
+to inject javascript; this was also blocked.
+
+This hole was discovered on 10 February 2008 and fixed the same day
+with the release of ikiwiki 2.31.1. (And a few subsequent versions..)
+A fix was also backported to Debian etch, as version 1.33.4. I recommend
+upgrading to one of these versions if your wiki can be edited by third
+parties.