# CVE-2020-28169: Privilege escalation in n/a

> Attackers can escalate privileges to SYSTEM by exploiting writable bin directory permissions in the td-agent-builder plugin for Fluentd.

- **Severity:** High 7.0 (`CVSS:3.1/AV:L/AC:H/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-qh64-cxhv-8756

## What is CVE-2020-28169?

CVE-2020-28169 is a high-severity vulnerability in Debian Debian Linux, published on 24 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The td-agent-builder plugin before 2020-12-18 for Fluentd allows attackers to gain privileges because the bin directory is writable by a user account, but a file in bin is executed as NT AUTHORITY\SYSTEM.

Weakness: CWE-732 (Incorrect Permission Assignment for Critical Resource)

## Which versions are affected by CVE-2020-28169?

It affects 2 products.


Products: Debian Debian Linux, Td-Agent-Builder Project Td-Agent-Builder.

## How do I fix CVE-2020-28169?

No fix has been published for CVE-2020-28169 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-28169 being exploited?

There is no known exploitation of CVE-2020-28169 in the wild and no public exploit code.

Public exploit code:

- Insecure Folder permission that lead to privilege escalation (github_poc): https://github.com/zubrahzz/FluentD-TD-agent-Exploit-CVE-2020-28169
- Fluentd TD-agent plugin 4.0.1 - Insecure Folder Permission (exploitdb)

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-28169 and fix it if it is affected.

What it is: CVE-2020-28169 is a high-severity vulnerability in Debian Debian Linux, published on 24 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-28169 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2020-28169/ (Markdown: https://insights.sbomify.com/CVE-2020-28169/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-28169
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-28169
- OSV: https://osv.dev/vulnerability/CVE-2020-28169

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-28169/
Summaries are generated and may contain mistakes; the official description above is the record.