CVE-2024-50691 Overview
CVE-2024-50691 affects the SunGrow iSolarCloud Android application versions V2.1.6.20241104 and prior. The app explicitly ignores SSL/TLS certificate errors, exposing communications to interception. Attackers positioned on the network path can impersonate the iSolarCloud server and intercept or manipulate traffic between the mobile app and backend services. The vulnerability is classified under CWE-295: Improper Certificate Validation.
iSolarCloud is used to monitor and manage SunGrow solar inverter installations. Compromised sessions can expose account credentials, device telemetry, and configuration data for connected energy assets.
Critical Impact
Missing certificate validation enables man-in-the-middle (MitM) attacks against iSolarCloud mobile users, allowing interception and tampering of solar fleet management traffic.
Affected Products
- SunGrow iSolarCloud Android app version V2.1.6.20241104
- All SunGrow iSolarCloud Android app versions prior to V2.1.6.20241104
- Deployments managing SunGrow solar inverters via the affected mobile client
Discovery Timeline
- 2025-02-26 - CVE-2024-50691 published to NVD
- 2025-04-07 - Last updated in NVD database
Technical Details for CVE-2024-50691
Vulnerability Analysis
The iSolarCloud Android app initiates HTTPS connections to SunGrow backend services but suppresses certificate validation errors. The TLS handshake completes regardless of whether the presented server certificate is trusted, valid, expired, or matches the expected hostname.
This behavior negates the authentication guarantees TLS is designed to provide. The encrypted channel still exists, but the client cannot verify it is talking to the real iSolarCloud server. An attacker who can present any certificate during the handshake can decrypt and modify application traffic.
The weakness commonly arises from custom TrustManager or HostnameVerifier implementations that accept all certificates, or from debug-only trust logic shipped in production builds.
Root Cause
The root cause is improper certificate validation [CWE-295]. The app overrides default Android TLS handling to accept any certificate chain presented by a server, removing the trust anchor check that protects against impersonation.
Attack Vector
An attacker must achieve a network-adjacent position relative to the victim. Practical scenarios include rogue Wi-Fi access points, ARP spoofing on shared networks, compromised upstream infrastructure, or DNS hijacking.
Once positioned, the attacker presents an attacker-controlled certificate during the TLS handshake. The iSolarCloud app accepts it, and the attacker proxies traffic between the app and the real server. Captured material can include authentication tokens, account credentials, plant identifiers, and inverter telemetry. The attacker can also inject modified responses to influence app behavior or displayed data.
The vulnerability mechanism is described in the Sungrow Security Notice #6124.
Detection Methods for CVE-2024-50691
Indicators of Compromise
- TLS connections from mobile devices to iSolarCloud endpoints terminating at unexpected certificate issuers or self-signed certificates.
- Unusual proxy or VPN configurations on devices running the iSolarCloud app.
- DNS responses for iSolarCloud domains resolving to non-SunGrow infrastructure ranges.
- Authentication anomalies on iSolarCloud accounts such as logins from unexpected geographies following mobile use on untrusted networks.
Detection Strategies
- Inspect outbound HTTPS traffic from managed mobile devices for SNI values matching iSolarCloud domains paired with certificates not issued by SunGrow's expected certificate authorities.
- Use mobile application analysis tools to verify whether installed iSolarCloud APKs contain permissive TrustManager or HostnameVerifier implementations.
- Correlate iSolarCloud login events with network telemetry to identify sessions initiated from untrusted Wi-Fi networks.
Monitoring Recommendations
- Monitor mobile device management (MDM) inventories for installed iSolarCloud versions and flag any at or below V2.1.6.20241104.
- Alert on captive portal or unknown CA certificate prompts on managed devices used to access solar infrastructure.
- Log and review authentication events on iSolarCloud accounts associated with operational technology assets.
How to Mitigate CVE-2024-50691
Immediate Actions Required
- Update the iSolarCloud Android app to the version released after V2.1.6.20241104 as published by SunGrow.
- Restrict use of the iSolarCloud app to trusted networks until the patched version is deployed.
- Rotate iSolarCloud account passwords for users who accessed the app on untrusted networks.
- Review account activity logs for unauthorized access or configuration changes on managed inverters.
Patch Information
SunGrow published guidance in the Sungrow Security Notice #6124. Users should install the latest iSolarCloud Android release from the official Google Play Store listing to receive the fixed certificate validation logic.
Workarounds
- Use the iSolarCloud app only over networks you control, such as a corporate VPN terminating in a trusted environment.
- Avoid using the app on public Wi-Fi, hotel networks, or other shared infrastructure until patched.
- Enforce certificate pinning at the network layer where feasible, or block iSolarCloud traffic from managed devices that have not been updated.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
