# CVE-2019-10120: Auth bypass in n/a

> Attackers can maintain unauthorized access by reusing session IDs after logout on HomeMatic CCU devices, leading to account takeover.

- **Severity:** High 8.8 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 10 Jul 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-qp96-5rrf-qmcp

## What is CVE-2019-10120?

CVE-2019-10120 is a high-severity authentication bypass vulnerability in n/a, published on 10 Jul 2019. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

On eQ-3 HomeMatic CCU2 devices before 2.41.8 and CCU3 devices before 3.43.16, automatic login configuration (aka setAutoLogin) can be achieved by continuing to use a session ID after a logout, aka HMCCU-154.

Weakness: CWE-384 (Session Fixation)

## Which versions are affected by CVE-2019-10120?

It affects 2 products.


Products: Eq-3 Ccu2 Firmware, Eq-3 Ccu3 Firmware.

## How do I fix CVE-2019-10120?

No fix has been published for CVE-2019-10120 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-10120 being exploited?

There is no known exploitation of CVE-2019-10120 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2019-10119](https://insights.sbomify.com/CVE-2019-10119/): Auth bypass in n/a (critical 9.8)
- [CVE-2019-10121](https://insights.sbomify.com/CVE-2019-10121/): Missing authorization in n/a (critical 9.8)
- [CVE-2019-10122](https://insights.sbomify.com/CVE-2019-10122/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-14423](https://insights.sbomify.com/CVE-2019-14423/): Command injection in n/a (high 8.8)
- [CVE-2019-14473](https://insights.sbomify.com/CVE-2019-14473/): Missing authorization in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-10120 and fix it if it is affected.

What it is: CVE-2019-10120 is a high-severity authentication bypass vulnerability in n/a, published on 10 Jul 2019. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-10120 in the wild and no public exploit code.

Affected product: n/a. 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-2019-10120/ (Markdown: https://insights.sbomify.com/CVE-2019-10120/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-10120
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-10120
- OSV: https://osv.dev/vulnerability/CVE-2019-10120

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-10120/
Summaries are generated and may contain mistakes; the official description above is the record.