# CVE-2023-34339: Information disclosure in Ktor

> Attackers can view sensitive authentication headers in exception messages, potentially exposing credentials in logs or error responses.

- **Severity:** Low 3.3 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **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:** 1 Jun 2023
- **Updated:** 8 Jan 2025
- **Also known as:** GHSA-w2c4-vpgj-g3jp

## What is CVE-2023-34339?

CVE-2023-34339 is a low-severity vulnerability in JetBrains Ktor, published on 1 Jun 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In JetBrains Ktor before 2.3.1 headers containing authentication data could be added to the exception's message

Weakness: CWE-209 (Generation of Error Message Containing Sensitive Information)

## Which versions are affected by CVE-2023-34339?

It affects 1 product.


Products: Jetbrains Ktor.

## How do I fix CVE-2023-34339?

No fix has been published for CVE-2023-34339 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-34339 being exploited?

There is no known exploitation of CVE-2023-34339 in the wild and no public exploit code.

## Other vulnerabilities in JetBrains Ktor

- [CVE-2019-12736](https://insights.sbomify.com/CVE-2019-12736/): Command injection in n/a (critical 9.8)
- [CVE-2022-29930](https://insights.sbomify.com/CVE-2022-29930/): SHA1 implementation in JetBrains Ktor Native 2.0.0 was returning the same value. (high 8.7)
- [CVE-2023-45612](https://insights.sbomify.com/CVE-2023-45612/): XML external entity in Ktor (high 8.6)
- [CVE-2022-48476](https://insights.sbomify.com/CVE-2022-48476/): Path traversal in Ktor (high 7.5)
- [CVE-2021-43203](https://insights.sbomify.com/CVE-2021-43203/): Auth bypass in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-34339 and fix it if it is affected.

What it is: CVE-2023-34339 is a low-severity vulnerability in JetBrains Ktor, published on 1 Jun 2023. 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-2023-34339 in the wild and no public exploit code.

Affected product: JetBrains Ktor. 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-2023-34339/ (Markdown: https://insights.sbomify.com/CVE-2023-34339/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-34339
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-34339
- OSV: https://osv.dev/vulnerability/CVE-2023-34339

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-34339/
Summaries are generated and may contain mistakes; the official description above is the record.