Answer in brief
CVE-2026-54603 records a High severity (CVSS 8.6) vulnerability in OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host. The current sources do not mark it as known exploited. The current feed maps ruby-oauth/oauth2 (generic), oauth2 (rubygems), oauth2 (rubygems). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.6. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps ruby-oauth/oauth2 (generic), oauth2 (rubygems), oauth2 (rubygems). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| ruby-oauth/oauth2generic | >=0.4.0 <2.0.22 | 2.0.22 |
| oauth2rubygems | >=0.4.0,<=2.0.21 | 2.0.22 |
| oauth2rubygems | >=0.4.0 <2.0.22 | 2.0.22 |
Published upstream
Jul 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 2, 2026
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.
Quoted source text, attributed separately from HOL analysis.