Headline
GHSA-2v3v-3whp-953h: starcitizentools/citizen-skin allows stored XSS in user registration date message
Summary
Various date messages returned by Language::userDate are inserted into raw HTML, allowing anybody who can edit those messages to insert arbitrary HTML into the DOM.
Details
The result of $this->lang->userDate( $timestamp, $this->user ) returns unescaped values, but is inserted as raw HTML by Citizen:
https://github.com/StarCitizenTools/mediawiki-skins-Citizen/blob/072e4365e9084e4b153eac62d3666566c06f5a49/includes/Components/CitizenComponentUserInfo.php#L55-L60
PoC
- Go to any page using citizen with the uselang parameter set to x-xss and while being logged in
Depending on the registration date of the account you’re logged in with, various messages can be shown. In my case, it’s
november:
Impact
This impacts wikis where a group has the editinterface but not the editsitejs user right.
Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.