Overview
CVE-2025-56400 details a Cross-Site Request Forgery (CSRF) vulnerability within the OAuth implementation of the Tuya SDK, specifically version 6.5.0 for Android and iOS. This flaw impacts the Tuya Smart and Smartlife mobile applications, as well as any other third-party applications that incorporate this vulnerable SDK. The vulnerability allows a malicious actor to potentially link their own Amazon Alexa account to a victim’s Tuya account without the victim’s explicit consent.
Technical Details
The vulnerability stems from a failure to properly validate the OAuth state parameter during the account linking process between Tuya and Amazon Alexa. This missing validation creates an opportunity for a CSRF-like attack. An attacker can craft a malicious authorization link and trick the victim into clicking it. Because the state parameter is not correctly verified, the attacker can successfully complete the OAuth flow on the victim’s behalf. This unauthorized linking grants the attacker control of the victim’s Tuya-connected devices through their own Alexa account.
Notably, this vulnerability affects users regardless of whether they have previously linked their Alexa account to their Tuya account. Furthermore, the Tuya application does not need to be actively running on the victim’s device at the time of exploitation. All that is required is for the victim to click on the malicious link while being logged into their Tuya account through the application.
CVSS Analysis
At the time of writing, a CVSS score is not yet available for CVE-2025-56400. However, given the potential impact, a high CVSS score is anticipated due to the potential for remote code execution capabilities afforded through device control. Awaiting official CVSS information.
Possible Impact
Successful exploitation of CVE-2025-56400 can have significant consequences for affected users. An attacker gaining unauthorized access to a victim’s Tuya-connected devices via Alexa could:
- Remotely control security cameras, potentially spying on the victim.
- Manipulate smart doorbells, eavesdropping on conversations or unlocking the door.
- Control smart door locks, gaining unauthorized access to the victim’s home.
- Disable or trigger smart alarms, causing disruption and potentially compromising security.
- Control other smart home devices, such as lights, thermostats, and appliances.
Mitigation and Patch Steps
The primary mitigation strategy is to update the Tuya SDK to a patched version that properly validates the OAuth state parameter. Contact Tuya support for the latest information on patched SDK versions and recommended update procedures.
For Developers:
- Update the Tuya SDK: Immediately update to the latest version of the Tuya SDK that addresses this vulnerability. Consult Tuya’s announcement for details.
- Implement Proper OAuth State Validation: Ensure the OAuth state parameter is properly validated during the account linking flow to prevent CSRF attacks.
- Educate Users: Inform your users about the potential risk and advise them to be cautious about clicking on suspicious links.
For Users:
- Be wary of suspicious links: Avoid clicking on any links related to linking your Tuya account to Alexa unless you initiated the process directly through the official Tuya or Alexa apps.
- Monitor Alexa activity: Regularly review your Alexa activity logs for any unauthorized access or device control.
- Enable Two-Factor Authentication (2FA): Wherever available, enable 2FA for your Tuya and Alexa accounts for enhanced security.
- Keep Your Apps Updated: Ensure both the Tuya Smart/Smartlife apps and the Alexa app are updated to the latest versions.
References
Tuya Official Website
Tuya Security Announcement (Related to Vulnerability)
NIST CVE Entry (Once Available)
