CVE-2026-50631

HIGH

Apache CXF: OAuth2: TOCTOU Race Condition in Refresh Token Processing

Title source: cna

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.

References (2)

Core 2

Core References

Vendor Advisory vendor-advisory

https://lists.apache.org/thread/s83t3x4r626o9h8rt0ryr1w7w53l1vv8

Mailing List

http://www.openwall.com/lists/oss-security/2026/06/11/8

Scores

CVSS v3 7.4

EPSS 0.0034

EPSS Percentile 26.1%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact total

Details

CWE

CWE-367

Status published

Products (3)

apache/cxf < 4.1.7

Apache Software Foundation/Apache CXF < 4.1.7

Apache Software Foundation/Apache CXF 4.2.0 - 4.2.2

Published Jun 12, 2026

Tracked Since Jun 12, 2026