SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-33637

Versions 2.0.0 through 2.14.1 still allow protocol-relative host override when the request target is passed as a URI object (rather than a String) to Faraday::Connection#build_exclusive_url.

MEDIUM 6.5EPSS 0.27%

Does this matter?

Lower severity and a low EPSS score (0.27%). Track it; it rarely justifies an emergency change on its own.

Description

Faraday is an HTTP client library abstraction layer that provides a common interface over many adapters. Versions 2.0.0 through 2.14.1 still allow protocol-relative host override when the request target is passed as a URI object (rather than a String) to Faraday::Connection#build_exclusive_url. This bypasses the February 2026 fix for GHSA-33mh-2634-fwr2 and enables off-host request forgery: a request built from a fixed-base Faraday::Connection can be redirected to an attacker-controlled host, forwarding connection-scoped values such as Authorization headers and default query parameters. This issue has been fixed in version 2.14.3.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS
0.27% probability · 20th percentile
CISA KEV
Not listed
Weakness
CWE-918
Affected
faraday project/faraday
Source
security-advisories@github.com

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