# CVE-2017-16689: Auth bypass in Trusted RFC connection

> Attackers can establish trusted RFC connections to unauthorized clients or users, bypassing authentication controls in SAP Kernel.

- **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:** 12 Dec 2017
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-crwv-5x5f-fc2f

## What is CVE-2017-16689?

CVE-2017-16689 is a high-severity authentication bypass vulnerability in SAP Trusted RFC connection, published on 12 Dec 2017. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A Trusted RFC connection in SAP KERNEL 32NUC, SAP KERNEL 32Unicode, SAP KERNEL 64NUC, SAP KERNEL 64Unicode 7.21, 7.21EXT, 7.22, 7.22EXT; SAP KERNEL from 7.21 to 7.22, 7.45, 7.49, can be established to a different client or a different user on the same system, although no explicit Trusted/Trusting Relation to the same system has been defined.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2017-16689?

It affects 1 product.


Products: Sap Sap Kernel.

## How do I fix CVE-2017-16689?

No fix has been published for CVE-2017-16689 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-16689 being exploited?

There is no known exploitation of CVE-2017-16689 in the wild and no public exploit code.

## Other vulnerabilities in SAP Trusted RFC connection

- [CVE-2019-0365](https://insights.sbomify.com/CVE-2019-0365/): Denial of service in SAP GUI for Java (BC-FES-JAV) (high 7.5)
- [CVE-2018-2433](https://insights.sbomify.com/CVE-2018-2433/): Denial of service in SAP Gateway (high 7.5)
- [CVE-2018-2360](https://insights.sbomify.com/CVE-2018-2360/): Missing authorization in SAP Startup Service (high 7.5)
- [CVE-2017-5997](https://insights.sbomify.com/CVE-2017-5997/): Denial of service in n/a (high 7.5)
- [CVE-2014-9594](https://insights.sbomify.com/CVE-2014-9594/): Memory corruption in n/a (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-16689 and fix it if it is affected.

What it is: CVE-2017-16689 is a high-severity authentication bypass vulnerability in SAP Trusted RFC connection, published on 12 Dec 2017. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2017-16689 in the wild and no public exploit code.

Affected product: SAP Trusted RFC connection. 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-2017-16689/ (Markdown: https://insights.sbomify.com/CVE-2017-16689/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-16689
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-16689
- OSV: https://osv.dev/vulnerability/CVE-2017-16689

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From sbomify Insights: https://insights.sbomify.com/CVE-2017-16689/
Summaries are generated and may contain mistakes; the official description above is the record.