# CVE-2021-20653: Missing authorization in Calsos CSDJ

> Remote attackers can bypass access restrictions to obtain unauthorized historical data from Calsos CSDJ devices without privileges.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Feb 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-2h56-v244-fqpv

## What is CVE-2021-20653?

CVE-2021-20653 is a medium-severity missing authorization vulnerability in NEC Platforms, Ltd. Calsos CSDJ, published on 17 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Calsos CSDJ (CSDJ-B 01.08.00 and earlier, CSDJ-H 01.08.00 and earlier, CSDJ-D 01.08.00 and earlier, and CSDJ-A 03.08.00 and earlier) allows remote attackers to bypass access restriction and to obtain unauthorized historical data without access privileges via unspecified vectors.

Weakness: CWE-276 (Incorrect Default Permissions)

## Which versions are affected by CVE-2021-20653?

It affects 4 products.


Products: Nec Csdj-a Firmware, Nec Csdj-B Firmware, Nec Csdj-D Firmware, Nec Csdj-H Firmware.

## How do I fix CVE-2021-20653?

No fix has been published for CVE-2021-20653 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20653 being exploited?

There is no known exploitation of CVE-2021-20653 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20653 and fix it if it is affected.

What it is: CVE-2021-20653 is a medium-severity missing authorization vulnerability in NEC Platforms, Ltd. Calsos CSDJ, published on 17 Feb 2021. 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-2021-20653 in the wild and no public exploit code.

Affected product: NEC Platforms, Ltd. Calsos CSDJ. 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-2021-20653/ (Markdown: https://insights.sbomify.com/CVE-2021-20653/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20653
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20653
- OSV: https://osv.dev/vulnerability/CVE-2021-20653

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20653/
Summaries are generated and may contain mistakes; the official description above is the record.