# CVE-2026-48598: CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injection

> Attackers can inject headers into multipart requests via unescaped disposition parameters, potentially altering request structure or content.

- **Severity:** Low 2.1 (`CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Jun 2026
- **Updated:** 24 Sep 2026
- **Also known as:** EEF-CVE-2026-48598, GHSA-28jh-g32x-v9v4

## What is CVE-2026-48598?

CVE-2026-48598 is a low-severity vulnerability in elixir-tesla tesla, published on 2 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Improper Encoding or Escaping of Output vulnerability in elixir-tesla tesla allows multipart part header injection via unescaped Content-Disposition parameter values.

Tesla.Multipart.part_headers_for_disposition/1 interpolates each disposition parameter as #{k}="#{v}" with no validation of CR (\r), LF (\n), or double-quote characters. The values come verbatim from the caller via Tesla.Multipart.add_field/4 (the name parameter), Tesla.Multipart.add_file/3, and Tesla.Multipart.add_file_content/4 (both the filename parameter and other disposition opts). A " in the value closes the quoted parameter early; a \r\n ends the Content-Disposition header line and starts a new part header (such as a forged Content-Type), or, after a second \r\n, ends the entire part header block and prepends bytes to the part body. The default-filename path in add_file/3 derives the filename via Path.basename/1, which does not strip CR or LF, so any application forwarding a partially-attacker-controlled file path inherits the same issue.

This issue affects tesla: from 0.8.0 before 1.18.3.

Weakness: CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2026-48598?

3 open source packages ship an affected version, including tesla. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `tesla` | Hex | From 0.8.0 | 1.18.3 |
| `tesla` | Hex | From 0.8.0 | 1.18.3 |
| `tesla` | Hex | From 0.8.0 | 1.18.3 |

Products: Elixir-Tesla Tesla.

## How do I fix CVE-2026-48598?

Upgrade tesla to 1.18.3 or later.

## Is CVE-2026-48598 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48598 exists.

Public exploit code:

- Patched google_gax 0.4.1 for Tesla 1.18.3+ compatibility (CVE-2026-48598) (github_poc): https://github.com/workshops-de/google_gax

## Other vulnerabilities in elixir-tesla tesla

- [CVE-2026-48594](https://insights.sbomify.com/CVE-2026-48594/): Decompression bomb in Tesla.Middleware.DecompressResponse and Tesla.Middleware.Compression (high 8.2)
- [CVE-2026-48595](https://insights.sbomify.com/CVE-2026-48595/): Authorization header leaks to third-party origin on cross-origin redirect in Tesla.Middleware.FollowRedirects (high 8.2)
- [CVE-2026-48597](https://insights.sbomify.com/CVE-2026-48597/): Atom table exhaustion via untrusted URL scheme in Tesla.Adapter.Mint (high 8.2)
- [CVE-2026-48596](https://insights.sbomify.com/CVE-2026-48596/): CRLF injection in Tesla.Multipart.add_content_type_param/2 allows HTTP header injection (low 2.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48598 and fix it if it is affected.

What it is: CVE-2026-48598 is a low-severity vulnerability in elixir-tesla tesla, published on 2 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48598 exists.

Affected packages and fixed versions:
- tesla (Hex): affected from 0.8.0; fixed in 1.18.3
- tesla (Hex): affected from 0.8.0; fixed in 1.18.3
- tesla (Hex): affected from 0.8.0; fixed in 1.18.3

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-2026-48598/ (Markdown: https://insights.sbomify.com/CVE-2026-48598/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48598
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48598
- OSV: https://osv.dev/vulnerability/CVE-2026-48598

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-48598/
Summaries are generated and may contain mistakes; the official description above is the record.