Elefant CMS 1.3.12-RC Cross Site Scripting
Posted on 18 February 2017
Security Advisory - Curesec Research Team 1. Introduction Affected Product: Elefant CMS 1.3.12-RC Fixed in: 1.3.13 Fixed Version https://github.com/jbroadway/elefant/releases/tag/ Link: elefant_1_3_13_rc Vendor Website: https://www.elefantcms.com/ Vulnerability XSS Type: Remote Yes Exploitable: Reported to 09/05/2016 vendor: Disclosed to 02/02/2017 public: Release mode: Coordinated Release CVE: n/a (not requested) Credits Tim Coen of Curesec GmbH 2. Overview Elefant is a content managment system written in PHP. In version 1.3.12-RC, it is vulnerable to multiple persistent as well as a reflected XSS issue. This allows an attacker to steal cookies, inject JavaScript keyloggers, or bypass CSRF protection. 3. Details Persistent XSS: Username CVSS: Medium 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N The username is echoed in various locations in the administration backend without encoding, leading to persistent XSS vulnerabilities. A user account is required, but the registration is open by default. Proof of Concept: 1. Register a new user (the registration is open by default). 2. Update the profile, as name use: Username<img src=no onerror=alert(1)> To trigger the payload: 1. Log in as admin 2. View the edit page for the user, for example: http://localhost/user/edit?id=3 Alternatively, the payload is also echoed on the page listing all users: http://localhost/admin/versions?id=&type=User As well as on the version page: http://localhost/admin/versions?type=User&id=3 Persistent XSS: Version Comparison CVSS: Medium 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N Various fields of various components are echoed unencoded when comparing versions of those components. Examples are the user profile fields Name, Address, Address 2, City, Title, Company, or About, or the Title, Menu Title, Window Title, Description, or Keyword of a page. Proof of Concept: The comparison page can for example be seen here: http://localhost/admin/ compare?id=8¤t=no Persistent XSS: Page & Content Block CVSS: Medium 4.0 AV:N/AC:L/Au:S/C:N/I:P/A:N The title of a new webpage is echoed unencoded, leading to persistent XSS. The same issue also exists when creating blocks. A user account with the right to create pages is required. By default, the editor role has this right. Proof of Concept: Create a new page or block, as title use: </title><img src=no onerror=alert(1)> The payload will be echoed in a title tag as well as a h1 tag when viewing the page and when editing the page. Persistent XSS: Blog Post CVSS: Medium 4.0 AV:N/AC:L/Au:S/C:N/I:P/A:N The title as well as the tags of a blog post are echoed unencoded, leading to persistent XSS. A user account with the right to create pages is required. By default, the editor role has this right Proof of Concept: Create a new blog post, as title and tag use: </title>'"><img src=no onerror= alert(1)> The payload will be echoed in a title tag, a h1 tag, as well as a href tag when viewing the page and when editing the page. Reflected XSS CVSS: Medium 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N The name parameter of the custom fields component is vulnerable to reflected XSS. Proof of Concept: GET /admin/extended?extends=User&name=%3Cimg%20src=no%20onerror=alert(1)%3E HTTP/1.1 4. Solution To mitigate this issue please upgrade at least to version 1.3.13. Please note that a newer version might already be available. 5. Report Timeline 09/05/2016 Informed Vendor about Issue, Vendor announces fix 11/07/2016 Asked Vendor if recent releases fixes issues, Vendor confirmed 02/02/2017 Disclosed to public Blog Reference: https://www.curesec.com/blog/article/blog/Elefant-CMS-1312-RC-Multiple-Persistent-and-Reflected-XSS-191.html -- blog: https://www.curesec.com/blog tweet: https://twitter.com/curesec Curesec GmbH Curesec Research Team Josef-Orlopp-StraAe 54 10365 Berlin, Germany
