Skip to content

Redirect allowed to protocol-relative URI

Moderate
flavorjones published GHSA-5jch-xhw4-r43v Aug 29, 2025

Package

bundler google_sign_in (RubyGems)

Affected versions

< 1.3.1

Patched versions

1.3.1

Description

Summary

It is possible to redirect a user to another origin if the "proceed_to" value in the session store is set to a protocol-relative URL.

Details

The google_sign_in gem persists an optional URL for redirection after authentication. If this URL is set to a protocol-relative URL, it improperly passes the "same origin" check, and it's possible for the user to be redirected to another origin after authentication, possibly resulting in exposure of authentication information if this attack is chained with other attacks.

Normally the value of this URL is only written and read by the library or the calling application. However, it may be possible to set this session value from a malicious site with a form submission.

Impact

Any Rails applications using the google_sign_in gem may be vulnerable, if this vector can be chained with another attack that is able to modify the OAuth2 request parameters.

Workarounds

No known workarounds.

Credits

This issue was responsibly reported by Hackerone user muntrive.

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N

CVE ID

CVE-2025-58067

Weaknesses

URL Redirection to Untrusted Site ('Open Redirect')

A web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a Redirect. This simplifies phishing attacks. Learn more on MITRE.