CVE-2026-54603

OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host

Published Jul 28, 2026 CVSS 3.1 · 8.6 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4822-1 ruby-oauth2 security update
Github GHSA Github GHSA GHSA-pp92-crg2-gfv9 OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Ruby-oauth
Ruby-oauth oauth2
Vendors & Products Ruby-oauth
Ruby-oauth oauth2
Type Values Removed Values Added
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.
Title OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host
Weaknesses CWE-200
CWE-601
References
Metrics cvssV3_1

{'score': 8.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 5, 2026, 5:06 PM
Reserved
Jun 15, 2026, 7:45 PM
Status
Awaiting Analysis
Published
Jul 28, 2026, 5:16 PM
Modified
Oct 23, 2026, 11:10 PM