mediawiki -- multiple vulnerabilities

The MediaWiki development team reports:

Certain unspecified input is not properly sanitised before being
returned to the user. This can be exploited to execute arbitrary HTML
and script code in a user’s browser session in context of an affected
site.
Certain unspecified input related to uploads is not properly
sanitised before being used. This can be exploited to inject arbitrary
HTML and script code, which will be executed in a user’s browser
session in context of an affected site when a malicious data is
opened. Successful exploitation may require that uploads are enabled
and the victim uses an Internet Explorer based browser.
Certain SVG scripts are not properly sanitised before being used.
This can be exploited to inject arbitrary HTML and script code, which
will be executed in a user’s browser session in context of an affected
site when a malicious data is opened. Successful exploitation may require
that SVG uploads are enabled and the victim uses a browser supporting SVG
scripting.
The application allows users to perform certain actions via HTTP
requests without performing any validity checks to verify the
requests. This can be exploited to perform certain operations when a
logged in user visits a malicious site.