Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-27482 is a critical-severity Improper Authentication (CWE-287) vulnerability in Home-Assistant Home-Assistant. Its CVSS base score is 10.0 (Critical).
Operationally, ranked in the top 0.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2023-27482 is an authentication bypass vulnerability (CWE-287) affecting the Home Assistant Supervisor component. It allows remote, unauthenticated access to the Supervisor API in all installation types using Supervisor 2023.01.1 or earlier; containerized or manually installed Core-only deployments are unaffected. The flaw carries a CVSS 3.1 score of 10.0.
An attacker with network access to an exposed Home Assistant instance can invoke Supervisor API endpoints without credentials, resulting in full compromise of confidentiality, integrity, and availability on the managed host.
Official advisories state the issue was fixed in Supervisor 2023.03.1, which was automatically deployed to all affected systems, and in Home Assistant Core 2023.3.0. Operators unable to upgrade are advised to avoid exposing the instance to the internet. Detailed technical write-ups are available from the elttam disclosure and the GitHub Security Advisory.
The associated EPSS score stands at 0.9061 with no subsequent rise indicated.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-31251
Vulnerability Data
homeassistant is an open source home automation tool. A remotely exploitable vulnerability bypassing authentication for accessing the Supervisor API through Home Assistant has been discovered. This impacts all Home Assistant installation types that use the Supervisor 2023.01.1 or older. Installation…
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types, like Home Assistant Container (for example Docker), or Home Assistant Core manually in a Python environment, are not affected. The issue has been mitigated and closed in Supervisor version 2023.03.1, which has been rolled out to all affected installations via the auto-update feature of the Supervisor. This rollout has been completed at the time of publication of this advisory. Home Assistant Core 2023.3.0 included mitigation for this vulnerability. Upgrading to at least that version is thus advised. In case one is not able to upgrade the Home Assistant Supervisor or the Home Assistant Core application at this time, it is advised to not expose your Home Assistant instance to the internet.
- CWE(s)
Related Threats
CVEs Like This One
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.
Detects unauthorized successful logons resulting from improper authentication implementations.
Documented procedures ensure personnel are trained on authentication mechanisms, tangibly lowering the risk of improper authentication being exploited.
Security awareness training instructs users on secure authentication practices and avoiding credential compromise.
Training on authentication mechanisms and best practices decreases the occurrence of improper authentication.
Non-repudiation requires strong authentication mechanisms to irrefutably attribute performed actions to specific individuals or processes.
Session content review can reveal authentication bypasses or failures in session establishment.
Review of authentication-related audit records can detect improper authentication mechanisms or bypasses.
Assessments check authentication mechanisms for correct implementation and effectiveness, reducing successful authentication bypass attempts.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.
A.5.17 directly mandates generation of non-guessable unique secrets, secure transmission, immediate change of defaults/temporary creds, strong password enforcement, no-reuse, and compromise response, which stops most improper-authentication exploits at source; the bounded remainder is non-password authentication methods and sufficiency-of-proof cases (e.g. IA-2/IA-5 enhancements) left to other controls.
Security requirements specified early and verified through testing drive the consistent implementation of authentication mechanisms, decreasing the likelihood that authentication steps are omitted or incorrectly applied.
A.8.26 explicitly requires identifying and addressing authentication-related requirements (including level of trust in identity via 8.5 and 5.17) as part of application development or acquisition, which prevents a slice of CWE-287 but leaves the dominant sufficiency-of-proof aspects (IA-2/IA-5) and many implementation defects untouched.
A.8.27 mandates security-by-design principles (least privilege, default-deny, never-trust/always-verify, MFA, end-to-end encryption of requests, distrust-external-input, secure session control, and explicit authentication/authorization in every layer), which directly stops most improper-authentication flaws from being exploitable; the bounded remainder is insufficient-proof cases that live only in the strength or correctness of the credential itself (IA-5/IA-2 territory).
A.8.5 directly mandates appropriate-strength authentication techniques, MFA for critical systems, protected log-on procedures, brute-force resistance, no cleartext passwords/transmission, and session controls that stop exploitation of insufficient proof of identity; the bounded remainder is cases where the chosen technique itself is flawed or insufficiently implemented (e.g. weak biometrics without fallback).
Hardening callouts derived
DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.