Vulnerability · Published Jun 2, 2026 · Assigned by EEF
CVE-2026-48598CRLF injection in Tesla.Multipart disposition parameters allows multipart part header injection
Low 2.1
In plain English
A low-severity security flaw in tesla from elixir-tesla. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| elixir-tesla | tesla | 0.8.0 – before 1.18.3 |
| elixir-tesla | tesla | 6ebfdb9abe9c6f119408045b933d82462decd351 – before bb1a2c3da2775924d96e3db8e315dcc4d5d2246e |
Weakness: CWE-116 · Vector: 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