CVE-2025-25305

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.

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.

Summary

Problem: Potential man-in-the-middle attacks due to missing SSL certificate verification in the project codebase and used third-party libraries.

Details

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.

Example: https://github.com/home-assistant/core/blob/c4411914c2e906105b765c00af5740bd0880e946/homeassistant/components/discord/notify.py#L84

When you scan the libraries used by the integrations in Home Assistant, you will find more issues like this.

The general handling in Home Assistant looks good, as homeassistant.helpers.aoihttp_client._async_get_connector handles it correctly.

PoC

1. Check that expired.badssl.com:443 gives an SSL error in when connecting with curl or browser.
2. Add the integration adguard with the setting host=expired.badssl.com, port=443, use-ssl=true, verify-ssl=true.
3. Check the logs - you get a HTTP 403 response.

Expected behavior:

1. The integration log shows an ssl.SSLCertVerificationError.

The following code shows the problem with ssl=True. No exception is raised when ssl=True (Python 3.11.6).

import asyncio
from ssl import SSLCertVerificationError

import aiohttp

BAD_URL = "https://expired.badssl.com/"


async def run_request(verify_ssl, result_placeholder: str):
    async with aiohttp.ClientSession() as session:
        exception_fired: bool = False
        try:
            await session.request("OPTIONS", BAD_URL, ssl=verify_ssl)
        except SSLCertVerificationError:
            exception_fired = True
        except Exception as error:
            print(error)
        else:
            exception_fired = False
        print(result_placeholder.format(exception_result=exception_fired))


# Case 1: ssl=False --> expected result: No exception
asyncio.run(run_request(False, "Test case 1: expected result: False - result: {exception_result}"))

# Case 2: ssl=None --> expected result: Exception
asyncio.run(run_request(None, "Test case 2: expected result: True - result: {exception_result}"))

# Case 3: ssl=True --> expected result: No Exception
asyncio.run(run_request(True, "Test case 3: expected result: False - result: {exception_result}"))

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.

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.

Summary

Problem: Potential man-in-the-middle attacks due to missing SSL certificate verification in the project codebase and used third-party libraries.

Details

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.

Example: https://github.com/home-assistant/core/blob/c4411914c2e906105b765c00af5740bd0880e946/homeassistant/components/discord/notify.py#L84

When you scan the libraries used by the integrations in Home Assistant, you will find more issues like this.

The general handling in Home Assistant looks good, as homeassistant.helpers.aoihttp_client._async_get_connector handles it correctly.

PoC

1. Check that expired.badssl.com:443 gives an SSL error in when connecting with curl or browser.
2. Add the integration adguard with the setting host=expired.badssl.com, port=443, use-ssl=true, verify-ssl=true.
3. Check the logs - you get a HTTP 403 response.

Expected behavior:

1. The integration log shows an ssl.SSLCertVerificationError.

The following code shows the problem with ssl=True. No exception is raised when ssl=True (Python 3.11.6).

import asyncio
from ssl import SSLCertVerificationError

import aiohttp

BAD_URL = "https://expired.badssl.com/"


async def run_request(verify_ssl, result_placeholder: str):
    async with aiohttp.ClientSession() as session:
        exception_fired: bool = False
        try:
            await session.request("OPTIONS", BAD_URL, ssl=verify_ssl)
        except SSLCertVerificationError:
            exception_fired = True
        except Exception as error:
            print(error)
        else:
            exception_fired = False
        print(result_placeholder.format(exception_result=exception_fired))


# Case 1: ssl=False --> expected result: No exception
asyncio.run(run_request(False, "Test case 1: expected result: False - result: {exception_result}"))

# Case 2: ssl=None --> expected result: Exception
asyncio.run(run_request(None, "Test case 2: expected result: True - result: {exception_result}"))

# Case 3: ssl=True --> expected result: No Exception
asyncio.run(run_request(True, "Test case 3: expected result: False - result: {exception_result}"))

Summary

Problem: Potential man-in-the-middle attacks due to missing SSL certificate verification in the project codebase and used third-party libraries.

Details

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.

Example: https://github.com/home-assistant/core/blob/c4411914c2e906105b765c00af5740bd0880e946/homeassistant/components/discord/notify.py#L84

When you scan the libraries used by the integrations in Home Assistant, you will find more issues like this.

The general handling in Home Assistant looks good, as homeassistant.helpers.aoihttp_client._async_get_connector handles it correctly.

PoC

1. Check that expired.badssl.com:443 gives an SSL error in when connecting with curl or browser.
2. Add the integration adguard with the setting host=expired.badssl.com, port=443, use-ssl=true, verify-ssl=true.
3. Check the logs - you get a HTTP 403 response.

Expected behavior:

1. The integration log shows an ssl.SSLCertVerificationError.

The following code shows the problem with ssl=True. No exception is raised when ssl=True (Python 3.11.6).

import asyncio
from ssl import SSLCertVerificationError

import aiohttp

BAD_URL = "https://expired.badssl.com/"


async def run_request(verify_ssl, result_placeholder: str):
    async with aiohttp.ClientSession() as session:
        exception_fired: bool = False
        try:
            await session.request("OPTIONS", BAD_URL, ssl=verify_ssl)
        except SSLCertVerificationError:
            exception_fired = True
        except Exception as error:
            print(error)
        else:
            exception_fired = False
        print(result_placeholder.format(exception_result=exception_fired))


# Case 1: ssl=False --> expected result: No exception
asyncio.run(run_request(False, "Test case 1: expected result: False - result: {exception_result}"))

# Case 2: ssl=None --> expected result: Exception
asyncio.run(run_request(None, "Test case 2: expected result: True - result: {exception_result}"))

# Case 3: ssl=True --> expected result: No Exception
asyncio.run(run_request(True, "Test case 3: expected result: False - result: {exception_result}"))