Vulnerabilities > CVE-2023-45135 - Improper Encoding or Escaping of Output vulnerability in Xwiki

047910
CVSS 8.0 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
network
low complexity
xwiki
CWE-116
NVD
Published: 2023-10-25
Updated: 2024-11-21

Summary

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. In `org.xwiki.platform:xwiki-platform-web` versions 7.2-milestone-2 until 14.10.12 and `org.xwiki.platform:xwiki-platform-web-templates` prior to versions 14.10.12 and 15.5-rc-1, it is possible to pass a title to the page creation action that isn't displayed at first but then executed in the second step. This can be used by an attacker to trick a victim to execute code, allowing script execution if the victim has script right or remote code execution including full access to the XWiki instance if the victim has programming right. For the attack to work, the attacker needs to convince the victim to visit a link like `<xwiki-host>/xwiki/bin/create/NonExistingSpace/WebHome?title=$services.logging.getLogger(%22foo%22).error(%22Script%20executed!%22)` where `<xwiki-host>` is the URL of the Wiki installation and to then click on the "Create" button on that page. The page looks like a regular XWiki page that the victim would also see when clicking the button to create a page that doesn't exist yet, the malicious code is not displayed anywhere on that page. After clicking the "Create" button, the malicious title would be displayed but at this point, the code has already been executed and the attacker could use this code also to hide the attack, e.g., by redirecting the victim again to the same page with an innocent title. It thus seems plausible that this attack could work if the attacker can place a fake "create page" button on a page which is possible with edit right. This has been patched in `org.xwiki.platform:xwiki-platform-web` version 14.10.12 and `org.xwiki.platform:xwiki-platform-web-templates` versions 14.10.12 and 15.5-rc-1 by displaying the title already in the first step such that the victim can notice the attack before continuing. It is possible to manually patch the modified files from the patch in an existing installation. For the JavaScript change, the minified JavaScript file would need to be obtained from a build of XWiki and replaced accordingly.

Vulnerable Configurations

Part Description Count
Application
Xwiki
305

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Cross Zone Scripting
    An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
  • Embedding Scripts in Non-Script Elements
    This attack is a form of Cross-Site Scripting (XSS) where malicious scripts are embedded in elements that are not expected to host scripts such as image tags (<img>), comments in XML documents (< !-CDATA->), etc. These tags may not be subject to the same input validation, output validation, and other content filtering and checking routines, so this can create an opportunity for an attacker to tunnel through the application's elements and launch a XSS attack through other elements. As with all remote attacks, it is important to differentiate the ability to launch an attack (such as probing an internal network for unpatched servers) and the ability of the remote attacker to collect and interpret the output of said attack.
  • Simple Script Injection
    An attacker embeds malicious scripts in content that will be served to web browsers. The goal of the attack is for the target software, the client-side browser, to execute the script with the users' privilege level. An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute code and scripts. Web browsers, for example, have some simple security controls in place, but if a remote attacker is allowed to execute scripts (through injecting them in to user-generated content like bulletin boards) then these controls may be bypassed. Further, these attacks are very difficult for an end user to detect.
  • User-Controlled Filename
    An attack of this type involves an attacker inserting malicious characters (such as a XSS redirection) into a filename, directly or indirectly that is then used by the target software to generate HTML text or other potentially executable content. Many websites rely on user-generated content and dynamically build resources like files, filenames, and URL links directly from user supplied data. In this attack pattern, the attacker uploads code that can execute in the client browser and/or redirect the client browser to a site that the attacker owns. All XSS attack payload variants can be used to pass and exploit these vulnerabilities.
  • Web Logs Tampering
    Web Logs Tampering attacks involve an attacker injecting, deleting or otherwise tampering with the contents of web logs typically for the purposes of masking other malicious behavior. Additionally, writing malicious data to log files may target jobs, filters, reports, and other agents that process the logs in an asynchronous attack pattern. This pattern of attack is similar to "Log Injection-Tampering-Forging" except that in this case, the attack is targeting the logs of the web server and not the application.

References