CVE-2026-63687

critical · 9.1

Apache CXF's JwtRequestCodeFilter copies all claims from a signed request JWT into the authorization parameter map without excluding security-sensitive parameters. A client that can produce a validly-signed request JWT (e.g., one whose client_secret is known or compromised) can thereby substitute the code_challenge, code_challenge_method, nonce, and state values that were set in the outer HTTP request, undermining PKCE integrity and OpenID Connect replay protection. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

9.1

CVSS

0.3%

EPSS (exploit prob.)

19th

EPSS percentile

2026-08-06

Published

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

Weaknesses

CWE-345

Affected products

Vendor	Product	Affected versions
apache	cxf	< 3.6.12
apache	cxf	>= 4.0.0, < 4.1.8
apache	cxf	>= 4.2.0, < 4.2.3

Check a specific version with /api/v1/cve/match.

References

https://lists.apache.org/thread/drcq4chmt0btx86f17o47j17r378hzpw
http://www.openwall.com/lists/oss-security/2026/08/06/22

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-63687