Severity: low Affected versions:
- Apache CXF (org.apache.cxf:cxf-rt-rs-security-oauth2) 4.2.0 before 4.2.2 - Apache CXF (org.apache.cxf:cxf-rt-rs-security-oauth2) before 4.1.7 Description: A race condition in AbstractOAuthDataProvider allows concurrent requests using the same Refresh Token to bypass single-use semantics and generate multiple valid Access Tokens, when 'recycleRefreshTokens' is set to false. A leaked refresh token can be replayed concurrently by multiple attackers or threads. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fixes this issue. Credit: Guanping Zhang reported this vulnerability. (finder) References: https://cxf.apache.org/ https://www.cve.org/CVERecord?id=CVE-2026-50631
