CyberSecBulletin
CVE-2025-25305NVD status: Deferred

core: Improper Verification of Source of a Communication Channel

CVE-2025-25305 is a high-severity improper verification of source of a communication channel vulnerability in core from Home-assistant, with a CVSS 3.1 base score of 7.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected core versions: < 2024.1.6. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.25% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of core you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Home-assistantcore< 2024.1.6Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
LowLimited modification of data is possible.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L. Scored by CNA (github.com).

Official description

Home Assistant Core is an open source home automation that puts local control and privacy first. Affected versions are subject to a potential man-in-the-middle attacks due to missing SSL certificate verification in the project codebase and used third-party libraries. In the past, `aiohttp-session`/`request` had the parameter `verify_ssl` to control SSL certificate verification. This was a boolean value. In `aiohttp` 3.0, this parameter was deprecated in favor of the `ssl` parameter. Only when `ssl` is set to `None` or provided with a correct configured SSL context the standard SSL certificate verification will happen. When migrating integrations in Home Assistant and libraries used by Home Assistant, in some cases the `verify_ssl` parameter value was just moved to the new `ssl` parameter. This resulted in these integrations and 3rd party libraries using `request.ssl = True`, which unintentionally turned off SSL certificate verification and opened up a man-in-the-middle attack vector. This issue has been addressed in version 2024.1.6 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Verification of Source of a Communication Channel

The product establishes a communication channel to handle an incoming request that has been initiated by an actor, but it does not properly verify that the request is coming from the expected origin.

How developers prevent this class of flaw

  • Use a mechanism that can validate the identity of the source, such as a certificate, and validate the integrity of data to ensure that it cannot be modified in transit using an Adversary-in-the-Middle (AITM) attack. When designing functionality of actions in the URL scheme, consider whether the action should be accessible to all mobile applications, or if an allowlist of applications to interface with is appropriate.

More Improper Verification of Source of a Communication Channel vulnerabilities (CWE-940)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in core

All core vulnerabilities

Recent Improper Verification of Source of a Communication Channel vulnerabilities

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