Time-of-check Time-of-use (TOCTOU) Race Condition Affecting org.apache.cxf:cxf-rt-rs-security-oauth2 package, versions [,4.1.7)[4.2.0,4.2.2)
Threat Intelligence
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- published15 Jun 2026
- disclosed12 Jun 2026
- creditGuanping Zhang
Introduced: 12 Jun 2026
CVE-2026-50631 (opens in a new tab)How to fix?
Upgrade org.apache.cxf:cxf-rt-rs-security-oauth2 to version 4.1.7, 4.2.2 or higher.
Overview
org.apache.cxf:cxf-rt-rs-security-oauth2 is a services framework.
Affected versions of this package are vulnerable to Time-of-check Time-of-use (TOCTOU) Race Condition due to a race condition in the AbstractOAuthDataProvider method when handling refresh tokens if the recycleRefreshTokens setting is set to false. An attacker can obtain multiple valid access tokens by concurrently replaying a leaked refresh token.