# CVE-2021-33900: StartTLS and SASL confidentiality protection bypass

> Attackers can bypass StartTLS and SASL confidentiality protections in Apache Directory Studio, exposing sensitive data in transit.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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:** Yes
- **Published:** 26 Jul 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-4x25-f45x-grv5, UBUNTU-CVE-2021-33900

## What is CVE-2021-33900?

CVE-2021-33900 is a high-severity vulnerability in Apache Directory Studio, published on 26 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

While investigating DIRSTUDIO-1219 it was noticed that configured StartTLS encryption was not applied when any SASL authentication mechanism (DIGEST-MD5, GSSAPI) was used. While investigating DIRSTUDIO-1220 it was noticed that any configured SASL confidentiality layer was not applied. This issue affects Apache Directory Studio version 2.0.0.v20210213-M16 and prior versions.

Weakness: CWE-319 (Cleartext Transmission of Sensitive Information), CWE-311 (Missing Encryption of Sensitive Data)

## Which versions are affected by CVE-2021-33900?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.apache.directory.studio:org.apache.directory.studio.parent` | Maven | All versions | 2.0.0.v20210717-M17 |
| `org.apache.directory.studio:org.apache.directory.studio.parent` | Maven | All versions | 2.0.0.v20210717-M17 |

Products: Apache Directory Studio.

## How do I fix CVE-2021-33900?

Upgrade org.apache.directory.studio:org.apache.directory.studio.parent to 2.0.0.v20210717-M17 or later.

## Is CVE-2021-33900 being exploited?

There is no known exploitation of CVE-2021-33900 in the wild and no public exploit code.

## Other vulnerabilities in Apache Directory Studio

- [CVE-2015-5349](https://insights.sbomify.com/CVE-2015-5349/): Apache Directory Studio Command Injection (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-33900 and fix it if it is affected.

What it is: CVE-2021-33900 is a high-severity vulnerability in Apache Directory Studio, published on 26 Jul 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-2021-33900 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.apache.directory.studio:org.apache.directory.studio.parent (Maven): affected all versions; fixed in 2.0.0.v20210717-M17
- org.apache.directory.studio:org.apache.directory.studio.parent (Maven): affected all versions; fixed in 2.0.0.v20210717-M17

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-2021-33900/ (Markdown: https://insights.sbomify.com/CVE-2021-33900/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-33900
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-33900
- OSV: https://osv.dev/vulnerability/CVE-2021-33900

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-33900/
Summaries are generated and may contain mistakes; the official description above is the record.