VulnerabilityDeferred

CVE-2026-48861

Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability in elixir-mint Mint allows HTTP Request Splitting and HTTP Request Smuggling.

LOW 2.1EPSS 0.17%

Does this matter?

Lower severity and a low EPSS score (0.17%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0: 2.1 LOWCVSS:4.0/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/M
EPSS: 0.17% probability · 6th percentile
CISA KEV: Not listed
Weakness: CWE-93
Source: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.