X-Git-Url: http://git.vanrenterghem.biz/git.ikiwiki.info.git/blobdiff_plain/2ad3e60ee8272b7cccfd83ae02d5b45e2cec003d..4729ff0812c1f3d06d98524e2fec232d3bf90513:/doc/security.mdwn?ds=sidebyside diff --git a/doc/security.mdwn b/doc/security.mdwn index 21aef316b..055e1d006 100644 --- a/doc/security.mdwn +++ b/doc/security.mdwn @@ -22,8 +22,8 @@ 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 in the CGI code. +I have been meaning to see if any CRLF injection type things can be +done in the CGI code. ---- @@ -110,7 +110,7 @@ runs ikiwiki to update a given wiki. The wrapper can in turn be made suid, for example to be used in a [[post-commit]] hook by people who cannot write to the html pages, etc. -If the wrapper script is made suid, then any bugs in this wrapper would be +If the wrapper program is made suid, then any bugs in this wrapper would be security holes. The wrapper is written as securely as I know how, is based on code that has a history of security use long before ikiwiki, and there's been no problem yet. @@ -162,10 +162,11 @@ 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 +If the [[plugins/template]] plugin is enabled, all users can modify templates +like any other part of the wiki. Some trusted users can modify templates +without it too. 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.) +allowed.) ---- @@ -177,7 +178,8 @@ 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 + from malformed image attacks for at least the formats listed in + `img_allowed_formats`. 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. @@ -439,3 +441,93 @@ with the release of ikiwiki 3.20100312. A fix was also backported to Debian etch, as version 2.53.5. I recommend upgrading to one of these versions if your wiki can be edited by third parties. + +## javascript insertion via insufficient htmlscrubbing of comments + +Kevin Riggle noticed that it was not possible to configure +`htmlscrubber_skip` to scrub comments while leaving unscubbed the text +of eg, blog posts. Confusingly, setting it to "* and !comment(*)" did not +scrub comments. + +Additionally, it was discovered that comments' html was never scrubbed during +preview or moderation of comments with such a configuration. + +These problems were discovered on 12 November 2010 and fixed the same +hour with the release of ikiwiki 3.20101112. ([[!cve CVE-2010-1673]]) + +## javascript insertion via insufficient checking in comments + +Dave B noticed that attempting to comment on an illegal page name could be +used for an XSS attack. + +This hole was discovered on 22 Jan 2011 and fixed the same day with +the release of ikiwiki 3.20110122. A fix was backported to Debian squeeze, +as version 3.20100815.5. An upgrade is recommended for sites +with the comments plugin enabled. ([[!cve CVE-2011-0428]]) + +## possible javascript insertion via insufficient htmlscrubbing of alternate stylesheets + +Giuseppe Bilotta noticed that 'meta stylesheet` directives allowed anyone +who could upload a malicious stylesheet to a site to add it to a +page as an alternate stylesheet, or replacing the default stylesheet. + +This hole was discovered on 28 Mar 2011 and fixed the same hour with +the release of ikiwiki 3.20110328. A fix was backported to Debian squeeze, +as version 3.20100815.6. An upgrade is recommended for sites that have +untrusted committers, or have the attachments plugin enabled. +([[!cve CVE-2011-1401]]) + +## tty hijacking via ikiwiki-mass-rebuild + +Ludwig Nussel discovered a way for users to hijack root's tty when +ikiwiki-mass-rebuild was run. Additionally, there was some potential +for information disclosure via symlinks. ([[!cve CVE-2011-1408]]) + +This hole was discovered on 8 June 2011 and fixed the same day with +the release of ikiwiki 3.20110608. Note that the fix is dependant on +a version of su that has a similar hole fixed. Version 4.1.5 of the shadow +package contains the fixed su; [[!debbug 628843]] tracks fixing the hole in +Debian. An upgrade is a must for any sites that have `ikiwiki-update-wikilist` +installed suid (not the default), and whose admins run `ikiwiki-mass-rebuild`. + +## javascript insertion via meta tags + +Raúl Benencia discovered an additional XSS exposure in the meta plugin. +([[!cve CVE-2012-0220]]) + +This hole was discovered on 16 May 2012 and fixed the same day with +the release of ikiwiki 3.20120516. A fix was backported to Debian squeeze, +as version 3.20100815.9. An upgrade is recommended for all sites. + +## XSS via openid selector + +Raghav Bisht discovered this XSS in the openid selector. ([[!cve CVE-2015-2793]]) + +The hole was reported on March 24th, a fix was developed on March 27th, +and the fixed version 3.20150329 was released on the 29th. A fix was backported +to Debian jessie as version 3.20141016.2 and to Debian wheezy as version +3.20120629.2. An upgrade is recommended for sites using CGI and openid. + +## XSS via error messages + +CGI error messages did not escape HTML meta-characters, potentially +allowing an attacker to carry out cross-site scripting by directing a +user to a URL that would result in a crafted ikiwiki error message. This +was discovered on 4 May by the ikiwiki developers, and the fixed version +3.20160506 was released on 6 May. The same fixes were backported to Debian +8 "jessie" in version 3.20141016.3. A backport to Debian 7 "wheezy" is +in progress. + +An upgrade is recommended for sites using +the CGI. ([[!cve CVE-2016-4561]], OVE-20160505-0012) + +## ImageMagick CVE-2016–3714 ("ImageTragick") + +ikiwiki 3.20160506 and 3.20141016.3 attempt to mitigate +[[!cve CVE-2016-3714]], and any +future ImageMagick vulnerabilities that resemble it, by restricting the +image formats that the [[ikiwiki/directive/img]] directive is willing to +resize. An upgrade is recommended for sites where an untrusted user is +able to attach images. Upgrading ImageMagick to a version where +CVE-2016-3714 has been fixed is also recommended, but at the time of +writing no such version is available.