Server-Side Request Forgery (SSRF) in faraday - CVE-2026-33637
Published: May 18, 2026
Vulnerability identifier: #VU131692
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-33637
CWE-ID: CWE-918
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: lostisland
Affected software:
faraday
faraday
Detailed vulnerability description
The vulnerability allows a remote attacker to redirect requests to an attacker-controlled host.
The vulnerability exists due to server-side request forgery in Faraday::Connection#build_exclusive_url when processing a protocol-relative URI object as a per-request target. A remote attacker can supply a crafted protocol-relative URI object to redirect requests to an attacker-controlled host.
Connection-scoped headers such as Authorization may be preserved on the off-host request.
How to mitigate CVE-2026-33637
Install security update from vendor's website.