Mailing List Archive

MediaWiki security release 1.16.3
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I would like to announce the release of MediaWiki 1.16.3, which is a
security release. Three security issues were discovered.

Masato Kinugawa discovered a cross-site scripting (XSS) issue, which
affects Internet Explorer clients only, and only version 6 and
earlier. Web server configuration changes are required to fix this
issue. Upgrading MediaWiki will only be sufficient for people who use
Apache with AllowOverride enabled.

Due to the diversity of uploaded files that we allow, MediaWiki does
not guarantee that uploaded files will be safe if they are interpreted
by the client as some arbitrary file type, such as HTML. We rely on
the web server to send the correct Content-Type header, and we rely on
the web browser to respect it. This XSS issue arises due to IE 6
looking for a file extension in the query string of the URL (i.e.
after the "?"), if no extension is found in path part of the URL.
Masato Kinugawa discovered that the file extension in the path part
can be hidden from IE 6 by substituting the "." with "%2E".

To fix this issue, configure your web server to deny requests with
URLs that have a path part ending in a dot followed by a dangerous
file extension. For example, in Apache with mod_rewrite:

RewriteEngine On
RewriteCond %{QUERY_STRING} \.[a-z]{1,4}$ [nocase]
RewriteRule . - [forbidden]

Upgrading MediaWiki is necessary to fix this issue in
dynamically-generated content. This issue is easier to exploit using
dynamically generated content, since it requires no special
privileges. Accounts on both public and private wikis can be
compromised by clicking a malicious link in an email or website. For
more details, see bug 28235.

Wikipedia user Suffusion of Yellow discovered a CSS validation error
in the wikitext parser. This is an XSS issue for Internet Explorer
clients, and a privacy loss issue for other clients since it allows
the embedding of arbitrary remote images. For more details, see bug 28450.

MediaWiki developer Happy-Melon discovered that the transwiki import
feature neglected to perform access control checks on form submission.
The transwiki import feature is disabled by default. If it is enabled,
it allows wiki pages to be copied from a remote wiki listed in
$wgImportSources. The issue means that any user can trigger such an
import to occur. For more details, see bug 28449.

The localisations were updated using content from


Patch to previous version (1.16.2), without interface text:
Interface text changes:

GPG signatures:

Public keys:

Version: GnuPG v1.4.10 (GNU/Linux)
Comment: Using GnuPG with Mozilla -


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