# CVE-2016-4407: Auth bypass in n/a

> Remote authenticated users can impersonate arbitrary users due to improper signature verification in the DSA algorithm implementation.

- **Severity:** Medium 6.5 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A: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:** 13 Oct 2016
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-vrcm-r83p-fhmh

## What is CVE-2016-4407?

CVE-2016-4407 is a medium-severity authentication bypass vulnerability in n/a, published on 13 Oct 2016. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The DSA algorithm implementation in SAP SAPCRYPTOLIB 5.555.38 does not properly check signatures, which allows remote authenticated users to impersonate arbitrary users via unspecified vectors, aka SAP Security Note 2223008.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2016-4407?

It affects 1 product.


Products: Sap Sapcryptolib.

## How do I fix CVE-2016-4407?

No fix has been published for CVE-2016-4407 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-4407 being exploited?

There is no known exploitation of CVE-2016-4407 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-4407 and fix it if it is affected.

What it is: CVE-2016-4407 is a medium-severity authentication bypass vulnerability in n/a, published on 13 Oct 2016. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2016-4407 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-2016-4407/ (Markdown: https://insights.sbomify.com/CVE-2016-4407/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-4407
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-4407
- OSV: https://osv.dev/vulnerability/CVE-2016-4407

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-4407/
Summaries are generated and may contain mistakes; the official description above is the record.