# CVE-2025-29756: MQTT implementation in Sungrow iSolarCloud allowed users to subscribe to all data of all connected inverters

> Authenticated users can subscribe to all MQTT topics to read encrypted data from all connected solar inverters due to insufficient topic restrictions.

- **Severity:** High 8.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/AU:Y`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Jun 2025
- **Updated:** 23 Jun 2025
- **Also known as:** GHSA-59wx-gr78-xr29

## What is CVE-2025-29756?

CVE-2025-29756 is a high-severity missing authorization vulnerability in SunGrow iSolarCloud, published on 11 Jun 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

SunGrow's back end users system  iSolarCloud https://isolarcloud.com  uses an MQTT service to transport data from the user's connected devices to the user's web browser. 
The MQTT server however did not have sufficient restrictions in place to limit the topics that a user could subscribe to. 
While the data that is transmitted through the MQTT server is encrypted and the credentials for the MQTT server are obtained though an API call, the credentials could be used to subscribe to any topic and the encryption key can be used to decrypt all messages received.
An attack with an account on iSolarCloud.com could extract MQTT credentials and the decryption key from the browser and then use an external program to subscribe to the topic '#' and thus recieve all messages from all connected devices.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2025-29756?


## How do I fix CVE-2025-29756?

No fix has been published for CVE-2025-29756 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-29756 being exploited?

There is no known exploitation of CVE-2025-29756 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-29756 and fix it if it is affected.

What it is: CVE-2025-29756 is a high-severity missing authorization vulnerability in SunGrow iSolarCloud, published on 11 Jun 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-29756 in the wild and no public exploit code.

Affected product: SunGrow iSolarCloud. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-29756/ (Markdown: https://insights.sbomify.com/CVE-2025-29756/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-29756
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-29756
- OSV: https://osv.dev/vulnerability/CVE-2025-29756

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-29756/
Summaries are generated and may contain mistakes; the official description above is the record.