# CVE-2020-15813: Improper Certificate Validation in Graylog

> Attackers can bypass authentication by intercepting traffic to a malicious LDAP server due to missing SSL certificate validation in Graylog.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/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:** 17 Jul 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-3gg9-f3vh-866f

## What is CVE-2020-15813?

CVE-2020-15813 is a high-severity authentication bypass vulnerability in n/a, published on 17 Jul 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Graylog before 3.3.3 lacks SSL Certificate Validation for LDAP servers. It allows use of an external user/group database stored in LDAP. The connection configuration allows the usage of unencrypted, SSL- or TLS-secured connections. Unfortunately, the Graylog client code (in all versions that support LDAP) does not implement proper certificate validation (regardless of whether the "Allow self-signed certificates" option is used). Therefore, any attacker with the ability to intercept network traffic between a Graylog server and an LDAP server is able to redirect traffic to a different LDAP server (unnoticed by the Graylog server due to the lack of certificate validation), effectively bypassing Graylog's authentication mechanism.

Weakness: CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2020-15813?

2 open source packages ship an affected version, including org.graylog:graylog-parent. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `org.graylog:graylog-parent` | Maven | All versions | 3.3.3 |
| `org.graylog:graylog-parent` | Maven | All versions | 3.3.3 |

Products: Graylog Graylog.

## How do I fix CVE-2020-15813?

Upgrade org.graylog:graylog-parent to 3.3.3 or later.

## Is CVE-2020-15813 being exploited?

There is no known exploitation of CVE-2020-15813 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2021-37759](https://insights.sbomify.com/CVE-2021-37759/): Information disclosure in n/a (critical 9.8)
- [CVE-2021-37760](https://insights.sbomify.com/CVE-2021-37760/): Information disclosure in n/a (critical 9.8)
- [CVE-2026-1435](https://insights.sbomify.com/CVE-2026-1435/): Incorrect management of session invalidation vulnerability in Graylog Web Interface (critical 9.3)
- [CVE-2025-53106](https://insights.sbomify.com/CVE-2025-53106/): Graylog vulnerable to privilege escalation through API tokens (high 8.8)
- [CVE-2024-24824](https://insights.sbomify.com/CVE-2024-24824/): graylog2-server vulnerable to instantiation of arbitrary classes triggered by API request (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-15813 and fix it if it is affected.

What it is: CVE-2020-15813 is a high-severity authentication bypass vulnerability in n/a, published on 17 Jul 2020. 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-2020-15813 in the wild and no public exploit code.

Affected packages and fixed versions:
- org.graylog:graylog-parent (Maven): affected all versions; fixed in 3.3.3
- org.graylog:graylog-parent (Maven): affected all versions; fixed in 3.3.3

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-2020-15813/ (Markdown: https://insights.sbomify.com/CVE-2020-15813/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-15813
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-15813
- OSV: https://osv.dev/vulnerability/CVE-2020-15813

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-15813/
Summaries are generated and may contain mistakes; the official description above is the record.