Review reviewHigh

CVE-2026-50631

Apache Software Foundation Apache CXF, cxf

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 or 3.6.12, which fixes this issue.

CVSS: 7.4
EPSS: -
CISA KEV: Not listed
Published: 2026.06.12

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 7.4

Vulnerability overview

Affected product and versions

Product: Apache Software Foundation Apache CXF, cxf
Affected versions: >= 4.2.0 < 4.2.2, >= 4.0.0 < 4.1.7, < 3.6.12
Fixed versions: 4.1.7, 4.2.2

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Apache Software Foundation Apache CXF, cxf and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE: CWE-367