CVE-2026-54603
OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host
HIGH 8.6EPSS 0.4%
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.
- Affected
- ruby-oauth · oauth2
- CVSS v3.1 GITHUB
- 8.6 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N - EPSS
- 0.45% chance of exploitation in the next 30 days, 38th percentile
- Published
- 2026-07-28
- Updated
- 2026-10-05