CVE-2023-41893 — homeassistant
MEDIUMCVE-2023-41893 is a medium-severity (CVSS 4.3) Information Exposure vulnerability in homeassistant. A fix is available for homeassistant — see the affected versions and patch details below.
Account takeover via auth_callback login in Home Assistant Core
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-41893.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-41893 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
homeassistantReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Part of the Cure53 security audit of Home Assistant.
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 the 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.
An attacker could increase the efficacy of this strategy by registering a nearly identical domain to homeassistant.local, which at first glance may appear legitimate and thereby obfuscate any malicious intentions.
Nonetheless, owing to the requirements for victim interaction and Home Assistant instance exposure to the Internet, this severity rating was consequently downgraded to Low.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | homeassistant | all versions | 2023.9.0pip install --upgrade 'homeassistant==2023.9.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for homeassistant, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update homeassistant to 2023.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-41893 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-41893 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-41893. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-41893 in your dependencies?
O3 Security finds CVE-2023-41893 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.