# CVE-2020-8809: Supply chain in n/a

> Man-in-the-middle attackers can modify unencrypted update downloads, leading to arbitrary code execution in GXDLMS Director.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 25 Feb 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-r58g-p5fc-5h6w

## What is CVE-2020-8809?

CVE-2020-8809 is a high-severity vulnerability in n/a, published on 25 Feb 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Gurux GXDLMS Director prior to 8.5.1905.1301 downloads updates to add-ins and OBIS code over an unencrypted HTTP connection. A man-in-the-middle attacker can prompt the user to download updates by modifying the contents of gurux.fi/obis/files.xml and gurux.fi/updates/updates.xml. Then, the attacker can modify the contents of downloaded files. In the case of add-ins (if the user is using those), this will lead to code execution. In case of OBIS codes (which the user is always using as they are needed to communicate with the energy meters), this can lead to code execution when combined with CVE-2020-8810.

Weakness: CWE-494 (Download of Code Without Integrity Check)

## Which versions are affected by CVE-2020-8809?

It affects 1 product.


Products: Gurux Device Language Message Specification Director.

## How do I fix CVE-2020-8809?

No fix has been published for CVE-2020-8809 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-8809 being exploited?

There is no known exploitation of CVE-2020-8809 in the wild and no public exploit code.

Public exploit code:

- CVE-2020-8809 and CVE-2020-8810 (github_poc): https://github.com/seqred-s-a/gxdlmsdirector-cve

## Other vulnerabilities in n/a

- [CVE-2020-8810](https://insights.sbomify.com/CVE-2020-8810/): Path traversal in n/a (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-8809 and fix it if it is affected.

What it is: CVE-2020-8809 is a high-severity vulnerability in n/a, published on 25 Feb 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-8809 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-2020-8809/ (Markdown: https://insights.sbomify.com/CVE-2020-8809/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-8809
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-8809
- OSV: https://osv.dev/vulnerability/CVE-2020-8809

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-8809/
Summaries are generated and may contain mistakes; the official description above is the record.