Home assistant is an open source home automation. The audit team’s analyses confirmed that the redirect_uri and client_id are alterable when logging in. Consequently, the code parameter utilized to fetch the access_token post-authentication will be sent to the URL specified in the aforementioned parameters. Since an arbitrary URL is permitted and homeassistant.local represents the preferred, default domain likely used and trusted by many users, an attacker could leverage this weakness to manipulate a user and retrieve account access. Notably, this attack strategy is plausible if the victim has exposed their Home Assistant to the Internet, since after acquiring the victim’s access_token the adversary would need to utilize it directly towards the instance to achieve any pertinent malicious actions. To achieve this compromise attempt, the attacker must send a link with a redirect_uri that they control to the victim’s own Home Assistant instance. In the eventuality the victim authenticates via said link, the attacker would obtain code sent to the specified URL in redirect_uri, which can then be leveraged to fetch an access_token. Pertinently, an attacker could increase the efficacy of this strategy by registering a near identical domain to homeassistant.local, which at first glance may appear legitimate and thereby obfuscate any malicious intentions. This issue has been addressed in version 2023.9.0 and all users are advised to upgrade. There are no known workarounds for this vulnerability.
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Home-assistant | Home-assistant | * | 2023.9.0 (excluding) |
There are many different kinds of mistakes that introduce information exposures. The severity of the error can range widely, depending on the context in which the product operates, the type of sensitive information that is revealed, and the benefits it may provide to an attacker. Some kinds of sensitive information include:
Information might be sensitive to different parties, each of which may have their own expectations for whether the information should be protected. These parties include:
Information exposures can occur in different ways:
It is common practice to describe any loss of confidentiality as an “information exposure,” but this can lead to overuse of CWE-200 in CWE mapping. From the CWE perspective, loss of confidentiality is a technical impact that can arise from dozens of different weaknesses, such as insecure file permissions or out-of-bounds read. CWE-200 and its lower-level descendants are intended to cover the mistakes that occur in behaviors that explicitly manage, store, transfer, or cleanse sensitive information.