CVE-2026-54603 Details
Description
OAuth2 is a Ruby wrapper for the OAuth 2.0 and 2.1 authorization frameworks, including OpenID Connect (OIDC). From 0.4.0 to 2.0.21, a protocol-relative redirect Location returned to OAuth2::Client#request overrides the request authority, so the bearer Authorization header is sent to an attacker-controlled host, leaking the credential. This issue is fixed in version 2.0.22.
A vulnerability in the OAuth2 Ruby library, specifically in versions 0.4.0 through 2.0.21, allows for cross-origin credential disclosure. When an application using this library's client requests an authorization server that responds with a protocol-relative redirect, the redirect can override the request's authority. This misconfiguration causes the 'Authorization' header, which contains bearer tokens, to be sent to an attacker-controlled host, thereby leaking sensitive credentials. The issue arises because protocol-relative URLs are treated as network-path references, replacing the original request authority with that of the attacker-controlled host.
Users can upgrade to OAuth2 version 2.0.22, which addresses this vulnerability by preventing protocol-relative redirects from altering the request authority and removing 'Authorization' headers from cross-origin redirects.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jul 29, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-200 | Exposure of Sensitive Information to an Unauthorized Actor | [email protected] |
| CWE-601 | URL Redirection to Untrusted Site ('Open Redirect') | [email protected] |
Affected Products
No affected product data is available for this CVE.
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 29, 2026 | CVE Modified | CISA-ADP |
| Jul 28, 2026 | New CVE Received | [email protected] |