CVE-2026-48596
LowCVSS 3.7Exploitation Probability (EPSS)
Low risk26th percentile - higher than 26% of all known CVEs
Summary
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.
Risk Assessment
An attacker can inject arbitrary HTTP headers, potentially leading to HTTP Request Splitting or HTTP Response Splitting attacks, which could enable session hijacking or response manipulation.
Recommendation
Update the Tesla library to version 1.18.3 or later.
Other vulnerabilities in Tesla
See all- CVE-2026-48597Medium
Resource exhaustion vulnerability in the Tesla library (Elixir) before version 1.18.3. Tesla.Adapter.Mint.open_conn/2 converts the URL scheme of every request to a BEAM atom without validation, potentially filling the atom table and crashing the VM. An attacker can influence the request URL via redirect features or webhooks.
- CVE-2026-48595Medium
Tesla library (Elixir) versions from 1.4.0 before 1.18.3 improperly handle case sensitivity in HTTP headers during cross-origin redirects. The Authorization header in canonical form (e.g., "Authorization") is not filtered, leading to credential leakage to a third-party origin.
- CVE-2026-48594High
Vulnerability in the Tesla library for Elixir (versions 0.6.0 up to before 1.18.3) due to improper handling of highly compressed data (decompression bomb). HTTP responses are decompressed without size limits, and multiple compression layers can lead to exponential data expansion, causing memory exhaustion and denial of service.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS