# CVE-2016-0733: The Admin UI in Apache Ranger before 0.5.1 does not properly handle authentication requests that lack a password

> Remote attackers can bypass authentication in Apache Ranger Admin UI by providing a valid username without a password.

- **Severity:** Critical 9.8 (`CVSS:3.0/AV:N/AC:L/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:** Yes
- **Published:** 12 Apr 2016
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-j84c-j8qm-g47r

## What is CVE-2016-0733?

CVE-2016-0733 is a critical authentication bypass vulnerability in n/a, published on 12 Apr 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Admin UI in Apache Ranger before 0.5.1 does not properly handle authentication requests that lack a password, which allows remote attackers to bypass authentication by leveraging knowledge of a valid username.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2016-0733?

2 open source packages ship an affected version, including org.apache.ranger:ranger. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.ranger:ranger` | Maven | All versions | 0.5.1 |
| `org.apache.ranger:ranger` | Maven | All versions | 0.5.1 |

Products: Apache Ranger.

## How do I fix CVE-2016-0733?

Upgrade org.apache.ranger:ranger to 0.5.1 or later.

## Is CVE-2016-0733 being exploited?

There is no known exploitation of CVE-2016-0733 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2026-28672](https://insights.sbomify.com/CVE-2026-28672/): Apache Ranger: OS Command Injection via Username in UnixUserGroupBuilder (critical 9.8)
- [CVE-2026-32227](https://insights.sbomify.com/CVE-2026-32227/): Apache Ranger: SQL Injection vulnerability in lookup functionality (critical 9.8)
- [CVE-2026-40920](https://insights.sbomify.com/CVE-2026-40920/): Apache Ranger: Privilege Escalation via URL Parameter (critical 9.8)
- [CVE-2026-42537](https://insights.sbomify.com/CVE-2026-42537/): Apache Ranger: Remote Code Execution via JDBC URL Injection (critical 9.8)
- [CVE-2026-44416](https://insights.sbomify.com/CVE-2026-44416/): Apache Ranger: Remote Code Execution via Arbitrary Class Instantiation (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-0733 and fix it if it is affected.

What it is: CVE-2016-0733 is a critical authentication bypass vulnerability in n/a, published on 12 Apr 2016. 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-2016-0733 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.ranger:ranger (Maven): affected all versions; fixed in 0.5.1
- org.apache.ranger:ranger (Maven): affected all versions; fixed in 0.5.1

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-2016-0733/ (Markdown: https://insights.sbomify.com/CVE-2016-0733/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-0733
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-0733
- OSV: https://osv.dev/vulnerability/CVE-2016-0733

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-0733/
Summaries are generated and may contain mistakes; the official description above is the record.