What is the CVSS score of CVE-2026-66060?

CVE-2026-66060 has a CVSS 3.1 base score of 7.1 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N. EPSS exploitation probability: 0.1%.

Which versions of Home Assistant Companion are affected by CVE-2026-66060?

Home Assistant Android Companion App (versions before 2026.8.1) permits any co-installed application on a mobile device to remotely trigger configured automations-including control of door locks and…. A patch is available.

How to fix or mitigate CVE-2026-66060?

Within 24 hours, identify all systems running Home Assistant Android Companion App and assess which configured automations control critical physical systems such as locks or alarms. Within 7 days, deploy patch version 2026.8.1 across all affected devices using your primary distribution mechanism (app store updates, enterprise management platform, or user communication), and verify that updates have been installed on at least 95% of systems. Within 30 days, audit access logs for any unauthorized automation triggers prior to patching, review and strengthen mobile device security policies to restrict untrusted application co-installation on devices running sensitive applications, and evaluate network-level security enhancements such as authentication requirements for automation commands targeting physical actuators.

Home Assistant Companion CVE-2026-66060

EUVD-2026-54654 HIGH

Missing Authorization (CWE-862)

2026-08-07 GitHub_M

Authentication Bypass Core Home Assistant

7.1

CVSS 3.1 · Vendor: GitHub_M

Severity by source

Vendor (GitHub_M) PRIMARY

7.1 HIGH

AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

vuln.today AI

7.1 HIGH

AV:L because the malicious app must co-reside on the device; PR:N because Android exported Activities require no caller permission; S:C/I:H because the integrity impact reaches the HA server beyond the app.

3.1 AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

4.0 AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N

Primary rating from Vendor (GitHub_M).

CVSS VectorVendor: GitHub_M

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

High

Availability

None

Lifecycle Timeline

Source Code Evidence Fetched

Aug 07, 2026 - 21:18 vuln.today

Analysis Generated

Aug 07, 2026 - 21:18 vuln.today

Patch available

Aug 07, 2026 - 21:02 EUVD

CVE Published

Aug 07, 2026 - 20:35 cve.org

HIGH 7.1

DescriptionCVE.org

Home Assistant is open source home automation software focused on local control and privacy. Prior to 2026.5.3, the Companion app treats tag links (NFC or QR) delivered through an OS-level routing mechanism as if they were physically scanned, without validating the calling app or prompting the user. As a result, any untrusted app on the device can forward an arbitrary tag to Home Assistant, causing it to execute the associated automation as though a legitimate user had scanned an authorized tag. This allows silent, unattended automation execution by untrusted local callers. This issue is fixed in version 2026.8.1.

AnalysisAI

Silent automation execution in the Home Assistant Android Companion App prior to 2026.8.1 allows any co-installed app on the device to trigger arbitrary HA automations by forwarding a crafted tag URL to an exported Activity without user confirmation. The flaw exists because TagReaderActivity accepted both physical NFC intents and OS-routed deep links identically, with no caller validation or approval prompt before dispatching the tag scan to the Home Assistant server. No public exploit has been identified at time of analysis, but the attack is unattended and can control physical actuators such as locks or alarms.

Technical ContextAI

The Home Assistant Android Companion App registered TagReaderActivity with android:exported='true' in its AndroidManifest.xml, handling both NfcAdapter.ACTION_NDEF_DISCOVERED (physical NFC) and Intent.ACTION_VIEW (deep link or app-forwarded tag). The pre-fix code path in TagReaderActivity extracted a tag ID from the incoming URI and immediately called scanTag() against all registered Home Assistant servers without distinguishing the caller's identity. Because Android allows any installed application to invoke exported Activities without declaring special permissions, a malicious co-installed app could send an arbitrary tag URL to this Activity. CWE-862 (Missing Authorization) describes this root cause precisely: the Activity lacked any check that the Intent originator was the OS NFC subsystem rather than an untrusted third-party app. The fix at commit 968b49c58e4eba4d06371a3f6e73198ec6c8d4a7 introduces a TagReaderViewModel with a TagReaderUiState.ApprovingTag sealed state, requiring explicit user approval via onAllowOnce or onAllowAlways before any server call is made, and adds android:launchMode='singleTask' with a custom android:taskAffinity to mitigate task-hijacking variants. The CPE cpe:2.3:a:home-assistant:core:*:*:*:*:*:*:*:* is listed by EUVD, though the vulnerable code resides in the Android Companion App repository, not the core Home Assistant server.

RemediationAI

Update the Home Assistant Android Companion App to version 2026.8.1 or later, which introduces a mandatory user-confirmation prompt for all tag intents received via Android Intent routing, regardless of whether they originate from physical NFC hardware or a third-party application. The upstream fix is confirmed in commit 968b49c58e4eba4d06371a3f6e73198ec6c8d4a7 in the android repository; the vendor advisory is at https://github.com/home-assistant/core/security/advisories/GHSA-2xqv-hwrf-983f. As a compensating control prior to patching, restrict the device to trusted applications only and audit installed apps for unexpected Intent-handling behavior; however, this does not eliminate the attack surface because the exported Activity remains callable by any resident app until the patch is applied. Restricting Android device enrollment to MDM-managed profiles can reduce the risk of malicious app installation but adds operational overhead and does not substitute for the patch.