CVE-2023-41893
Published: 20 October 2023
Summary
CVE-2023-41893 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Home-Assistant Home-Assistant. Its CVSS base score is 4.3 (Medium).
Operationally, ranked at the 49.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-0093
Vulnerability details
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…
more
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.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Automated marking applies security attributes to system outputs, making it harder for attackers to exploit unmarked sensitive information leading to unauthorized exposure.
Proper attribute retention and permitted-value enforcement limits unauthorized actors from accessing sensitive information lacking correct labels.
Prevents unauthorized exposure of sensitive information by prohibiting untrusted external systems from processing or storing it.
By enforcing authorization matching prior to sharing, the control reduces the risk of exposing sensitive information to unauthorized actors.
Review and removal of nonpublic information from publicly accessible systems directly prevents exposure of sensitive data to unauthorized actors.
Data mining protection mechanisms detect and block unauthorized bulk extraction of sensitive data, directly mitigating exposure to unauthorized actors.
Literacy training teaches users to recognize and avoid actions that result in unauthorized exposure of sensitive information.
Retaining and monitoring training records confirms personnel have completed privacy and security awareness training on handling sensitive data, reducing the chance of unauthorized exposure due to lack of knowledge.