Overview
During a penetration test, Trustwave Spiderlabs’ researchers, Jordan Hedges and Avery Warddhana - previously with Trustwave - identified two vulnerabilities in third-party software for Canon Medical’s Vitrea View (https://anz.medical.canon/). Vitrea View is a tool that uses the DICOM standard to view medical images. If exploited an attacker could access patient information and obtain additional access to various services associated with Vitrea View.
Findings
The first finding is an unauthenticated Reflected XSS in an error message. The error page located at /vitrea-view/error/ reflects all input after the /error/ subdirectory back to the user, with minor restrictions. Single and double quotes, as well as space characters appear to break the reflection. Using backticks (`) and base64 encoding avoids these restrictions, however, and importing remote scripts is possible.
Overall, exploiting the vulnerabilities is an easy endeavor.
The following proof of concept will pop up as an alert stating “Script Execution” after replacing HOST with the address of the server hosting the Vitrea View application:
hxxps://HOST/vitrea-view/error/Invalid%20session:%20%3Cimg%20src=x%20onerror=alert(atob(%60U2NyaXB0IEV4ZWN1dGlvbg==%60))%3E">
The second finding is a separate Reflected XSS in the Vitrea View Administrative panel. In order to access this panel, the attacker would typically attempt to socially engineer an existing administrator into clicking on a specially crafted link. The search for 'groupID', 'offset', and 'limit' in the 'Group and Users' page of the administration panel all reflect their input back to the user when text is entered instead of the expected numerical inputs. Like the previous finding, the reflected input is slightly restricted, as it does not allow spaces. Once an authenticated admin is coerced into visiting the affected URL, it is possible to create and modify the Python, JavaScript and Groovy scripts used by the Vitrea View application.
hxxps://HOST/vitrea-view/admin/authorization/users/all?_dc=1637817433453&groupId=%3Cimg/src=%271%27/onerror=alert(0)%3E&search=&page=2&offset=0&limit=18
These vulnerabilities were reported to Canon Medical as part of Trustwave SpiderLabs’s Responsible Disclosure process, and Canon Medical released a patch for these issues in version 7.7.6. We recommend all customers on version 7.x to update to the latest release. We always appreciate vendors like Canon Medical that approach the disclosure process with transparency and in the interest of the security of their products and users.
Summary
Trustwave SpiderLabs’ researchers identified two Reflected XSS vulnerabilities in Canon Medical’s Vitrea View. If exploited these vulnerabilities could be used to retrieve patient information, stored images, or scans, and modify information depending on privileges used during the session. Sensitive information and credentials for various services integrated with Vitrea View could be accessed, as well. These vulnerabilities were assigned CVE-2022-37461.
Reference
TWSL2022-003: Multiple XSS Vulnerabilities in Canon Medical Vitrea View
