CVE-2026-48861
CRLF injection in HTTP/1 request line via unvalidated method in Mint
Description
Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in elixir-mint Mint allows HTTP Request Splitting and HTTP Request Smuggling. In lib/mint/http1/request.ex, the encode_request_line/2 function splices the caller-supplied method and target arguments directly into the HTTP/1 request line without any character validation: [method, ?\s, target, " HTTP/1.1\r\n"]. An application that forwards attacker-controlled input as the HTTP method or target to Mint.HTTP.request/5 is therefore exposed to request-line CRLF injection: the attacker can terminate the request line early, inject arbitrary headers, and smuggle an entirely separate pipelined HTTP request onto the same TCP connection. Mint 1.7.0 introduced validate_request_target/2, which rejects CRLF and other control characters in the target by default and closes the path/query vector unless the caller opts out via skip_target_validation: true. The method field remains unvalidated, so the method-based injection is exploitable under the default Mint configuration on all versions. This issue affects mint: from 0.1.0 before 1.9.0.
INFO
Published Date :
June 2, 2026, 4:16 p.m.
Last Modified :
July 22, 2026, 7:10 p.m.
Remotely Exploit :
No
Source :
6b3ad84c-e1a6-4bf7-a703-f496b71e49db
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | LOW | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db | ||||
| CVSS 4.0 | LOW | 6b3ad84c-e1a6-4bf7-a703-f496b71e49db |
Solution
- Update elixir-mint Mint to the latest version.
- Validate all input used for HTTP request lines.
- Ensure skip_target_validation is set to false if not needed.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-48861.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-48861 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-48861
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-48861 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-48861 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Jul. 22, 2026
Action Type Old Value New Value Added Translation Title: mint de elixir-mint, Description: Neutralización incorrecta de secuencias CRLF ('Inyección CRLF') vulnerabilidad en elixir-mint Mint permite la división de solicitudes HTTP (HTTP Request Splitting) y el contrabando de solicitudes HTTP (HTTP Request Smuggling). En lib/mint/http1/request.ex, la función encode_request_line/2 inserta los argumentos de método y objetivo proporcionados por el llamador directamente en la línea de solicitud HTTP/1 sin ninguna validación de caracteres: [method, ?\s, target, " HTTP/1.1\r\n"]. Una aplicación que reenvía entrada controlada por el atacante como el método HTTP o el objetivo a Mint.HTTP.request/5 está, por lo tanto, expuesta a la inyección CRLF en la línea de solicitud: el atacante puede terminar la línea de solicitud prematuramente, inyectar encabezados arbitrarios y contrabandear una solicitud HTTP canalizada (pipelined) completamente separada en la misma conexión TCP. Mint 1.7.0 introdujo validate_request_target/2, que rechaza CRLF y otros caracteres de control en el objetivo por defecto y cierra el vector de ruta/consulta a menos que el llamador opte por no hacerlo a través de skip_target_validation: true. El campo del método permanece sin validar, por lo que la inyección basada en el método es explotable bajo la configuración predeterminada de Mint en todas las versiones. Este problema afecta a mint: desde 0.1.0 antes de 1.9.0. -
CVE Modified by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:2.3:a:elixir-mint:mint:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/elixir-mint/mint', 'vendor': 'elixir-mint', 'modules': ["'Elixir.Mint.HTTP1.Request'"], 'product': 'mint', 'versions': [{'status': 'affected', 'version': '0.1.0', 'lessThan': '1.9.0', 'versionType': 'semver'}], 'packageURL': 'pkg:hex/mint', 'packageName': 'mint', 'programFiles': ['lib/mint/http1/request.ex'], 'collectionURL': 'https://repo.hex.pm', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.Mint.HTTP1.Request':encode_request_line/2"}]}, {'cpes': ['cpe:2.3:a:elixir-mint:mint:*:*:*:*:*:*:*:*'], 'repo': 'https://github.com/elixir-mint/mint.git', 'vendor': 'elixir-mint', 'modules': ["'Elixir.Mint.HTTP1.Request'"], 'product': 'mint', 'versions': [{'status': 'affected', 'version': '8db1acff30b6a9433762c18b1e1f891b8c1f74f7', 'lessThan': 'fad091454cbb7449b19edb8e1fee12ca7cf28c3a', 'versionType': 'git'}], 'packageURL': 'pkg:github/elixir-mint/mint', 'packageName': 'elixir-mint/mint', 'programFiles': ['lib/mint/http1/request.ex'], 'collectionURL': 'https://github.com', 'defaultStatus': 'unaffected', 'programRoutines': [{'name': "'Elixir.Mint.HTTP1.Request':encode_request_line/2"}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-48861', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-02T18:11:46.297986Z'} -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 02, 2026
Action Type Old Value New Value Added Reference https://github.com/elixir-mint/mint/security/advisories/GHSA-2pg6-44cx-c49v -
New CVE Received by 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
Jun. 02, 2026
Action Type Old Value New Value Added Description Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in elixir-mint Mint allows HTTP Request Splitting and HTTP Request Smuggling. In lib/mint/http1/request.ex, the encode_request_line/2 function splices the caller-supplied method and target arguments directly into the HTTP/1 request line without any character validation: [method, ?\s, target, " HTTP/1.1\r\n"]. An application that forwards attacker-controlled input as the HTTP method or target to Mint.HTTP.request/5 is therefore exposed to request-line CRLF injection: the attacker can terminate the request line early, inject arbitrary headers, and smuggle an entirely separate pipelined HTTP request onto the same TCP connection. Mint 1.7.0 introduced validate_request_target/2, which rejects CRLF and other control characters in the target by default and closes the path/query vector unless the caller opts out via skip_target_validation: true. The method field remains unvalidated, so the method-based injection is exploitable under the default Mint configuration on all versions. This issue affects mint: from 0.1.0 before 1.9.0. Added CVSS V4.0 AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-93 Added Reference https://cna.erlef.org/cves/CVE-2026-48861.html Added Reference https://github.com/elixir-mint/mint/commit/fad091454cbb7449b19edb8e1fee12ca7cf28c3a Added Reference https://github.com/elixir-mint/mint/security/advisories/GHSA-2pg6-44cx-c49v Added Reference https://osv.dev/vulnerability/EEF-CVE-2026-48861