Description
In Apache CXF's OAuth2 Dynamic Client Registration endpoint, the authorization server accepts and stores the `scope` value supplied in the client registration request verbatim, without validating it against an AS-defined allowlist. This could lead to a client self-assigning privileged scopes at registration time. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.
Affected products
apache: cxf
References2
- lists.apache.org/thread/2l1r16g79tpxd7fzrzr2q9oscwrjgljs Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/08/06/21
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 1% percentile: 54 · as of 12 November 2026
- CWE
- CWE-304
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