CVE-2023-41896

Home assistant is an open source home automation. Whilst auditing the frontend code to identify hidden parameters, Cure53 detected `auth_callback=1`, which is leveraged by the WebSocket authentication logic in tandem with the `state` parameter. The state parameter contains the `hassUrl`, which is subsequently utilized to establish a WebSocket connection. This behavior permits an attacker to create a malicious Home Assistant link with a modified state parameter that forces the frontend to connect to an alternative WebSocket backend. Henceforth, the attacker can spoof any WebSocket responses and trigger cross site scripting (XSS). Since the XSS is executed on the actual Home Assistant frontend domain, it can connect to the real Home Assistant backend, which essentially represents a comprehensive takeover scenario. Permitting the site to be iframed by other origins, as discussed in GHSA-935v-rmg9-44mw, renders this exploit substantially covert since a malicious website can obfuscate the compromise strategy in the background. However, even without this, the attacker can still send the `auth_callback` link directly to the victim user. To mitigate this issue, Cure53 advises modifying the WebSocket code’s authentication flow. An optimal implementation in this regard would not trust the `hassUrl` passed in by a GET parameter. Cure53 must stipulate the significant time required of the Cure53 consultants to identify an XSS vector, despite holding full control over the WebSocket responses. In many areas, data from the WebSocket was properly sanitized, which hinders post-exploitation. The audit team eventually detected the `js_url` for custom panels, though generally, the frontend exhibited reasonable security hardening. This issue has been addressed in Home Assistant Core version 2023.8.0 and in the npm package home-assistant-js-websocket in version 8.2.0. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:home-assistant:home-assistant:*:*:*:*:*:*:*:*
cpe:2.3:a:home-assistant:home-assistant-js-websocket:*:*:*:*:*:node.js:*:*

History

21 Nov 2024, 08:21

Type Values Removed Values Added
CVSS v2 : unknown
v3 : 9.0
v2 : unknown
v3 : 7.1
References () https://github.com/home-assistant/core/security/advisories/GHSA-935v-rmg9-44mw - Not Applicable () https://github.com/home-assistant/core/security/advisories/GHSA-935v-rmg9-44mw - Not Applicable
References () https://github.com/home-assistant/core/security/advisories/GHSA-cr83-q7r2-7f5q - Vendor Advisory () https://github.com/home-assistant/core/security/advisories/GHSA-cr83-q7r2-7f5q - Vendor Advisory

26 Oct 2023, 16:18

Type Values Removed Values Added
References (MISC) https://github.com/home-assistant/core/security/advisories/GHSA-935v-rmg9-44mw - (MISC) https://github.com/home-assistant/core/security/advisories/GHSA-935v-rmg9-44mw - Not Applicable
References (MISC) https://github.com/home-assistant/core/security/advisories/GHSA-cr83-q7r2-7f5q - (MISC) https://github.com/home-assistant/core/security/advisories/GHSA-cr83-q7r2-7f5q - Vendor Advisory
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 9.0
CPE cpe:2.3:a:home-assistant:home-assistant-js-websocket:*:*:*:*:*:node.js:*:*
cpe:2.3:a:home-assistant:home-assistant:*:*:*:*:*:*:*:*
First Time Home-assistant
Home-assistant home-assistant
Home-assistant home-assistant-js-websocket
CWE CWE-345

19 Oct 2023, 23:15

Type Values Removed Values Added
New CVE

Information

Published : 2023-10-19 23:15

Updated : 2024-11-21 08:21


NVD link : CVE-2023-41896

Mitre link : CVE-2023-41896

CVE.ORG link : CVE-2023-41896


JSON object : View

Products Affected

home-assistant

  • home-assistant
  • home-assistant-js-websocket
CWE
CWE-345

Insufficient Verification of Data Authenticity