CVE-2026-48596 CRLF injection in Tesla.Multipart.add_content_type_param/2 allows HTTP header injection
Attackers can inject arbitrary HTTP headers into outbound requests via unvalidated CRLF sequences in multipart content type parameters.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-48596?
CVE-2026-48596 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 Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting') vulnerability in elixir-tesla tesla allows HTTP header injection via Tesla.Multipart.add_content_type_param/2.
Tesla.Multipart.add_content_type_param/2 appends caller-supplied strings to the multipart content_type_params list without validating for CR (\r) or LF (\n) characters. Tesla.Multipart.headers/1 then joins these params verbatim with "; " to construct the outgoing Content-Type header value. A param containing \r\n splits the header line, allowing arbitrary headers to be injected into the outbound HTTP request. Any application that forwards untrusted input (such as a user-supplied charset or parameter string) into add_content_type_param/2 is affected.
This issue affects tesla: from 0.8.0 before 1.18.3.
Weakness: CWE-113
Which versions are affected by CVE-2026-48596?
3 open source packages ship an affected version, including tesla. It affects 1 product.
| Package | 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 include Elixir-Tesla Tesla.
How do I fix CVE-2026-48596?
Upgrade tesla to 1.18.3 or later.
Is CVE-2026-48596 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48596 exists.
Other vulnerabilities in elixir-tesla tesla
- CVE-2026-48594 Decompression bomb in Tesla.Middleware.DecompressResponse and Tesla.Middleware.Compression
- CVE-2026-48595 Authorization header leaks to third-party origin on cross-origin redirect in Tesla.Middleware.FollowRedirects
- CVE-2026-48597 Atom table exhaustion via untrusted URL scheme in Tesla.Adapter.Mint
- CVE-2026-48598 CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injection
Sources
Also known as EEF-CVE-2026-48596, GHSA-q7jx-v53g-848w.