# CVE-2020-26176: Missing authorization in n/a

> Attackers can list attachments for any workitem by guessing document IDs due to missing access control checks on the API endpoint.

- **Severity:** Medium 4.3 (`CVSS:3.1/AC:L/AV:N/A:N/C:L/I:N/PR:L/S:U/UI:N`)
- **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:** 18 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-w664-p7q3-cm25

## What is CVE-2020-26176?

CVE-2020-26176 is a medium-severity missing authorization vulnerability in n/a, published on 18 Dec 2020. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue was discovered in tangro Business Workflow before 1.18.1. No (or broken) access control checks exist on the /api/document/<DocumentID>/attachments API endpoint. Knowing a document ID, an attacker can list all the attachments of a workitem, including their respective IDs. This allows the attacker to gather valid attachment IDs for workitems that do not belong to them.

Weakness: CWE-922 (Insecure Storage of Sensitive Information)

## Which versions are affected by CVE-2020-26176?

It affects 1 product.


Products: Tangro Business Workflow.

## How do I fix CVE-2020-26176?

No fix has been published for CVE-2020-26176 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-26176 being exploited?

There is no known exploitation of CVE-2020-26176 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2020-26174](https://insights.sbomify.com/CVE-2020-26174/): File upload in n/a (high 8.8)
- [CVE-2020-26175](https://insights.sbomify.com/CVE-2020-26175/): Missing authorization in n/a (medium 6.5)
- [CVE-2020-26178](https://insights.sbomify.com/CVE-2020-26178/): Missing authorization in n/a (medium 5.3)
- [CVE-2020-26171](https://insights.sbomify.com/CVE-2020-26171/): Missing authorization in n/a (medium 4.3)
- [CVE-2020-26177](https://insights.sbomify.com/CVE-2020-26177/): Missing authorization in n/a (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-26176 and fix it if it is affected.

What it is: CVE-2020-26176 is a medium-severity missing authorization vulnerability in n/a, published on 18 Dec 2020. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-26176 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-2020-26176/ (Markdown: https://insights.sbomify.com/CVE-2020-26176/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-26176
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-26176
- OSV: https://osv.dev/vulnerability/CVE-2020-26176

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-26176/
Summaries are generated and may contain mistakes; the official description above is the record.