high8.6
CVE-2026-54603
OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| rubygems | oauth2 | >= 0.4.0, <= 2.0.21 | 2.0.22 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-pp92-crg2-gfv9
- https://github.com/ruby-oauth/oauth2/security/advisories/GHSA-pp92-crg2-gfv9
- https://github.com/ruby-oauth/oauth2/commit/0f0a474f1b38453e119e660c2daca742d4378ce9
- https://github.com/ruby-oauth/oauth2/releases/tag/v2.0.22
- https://lists.debian.org/debian-lts-announce/2026/10/msg00014.html