CVE-2026-63687CWE-345

CVE-2026-63687

Critical · published August 6, 2026

CVSS v3.1
9.1
EPSS
0%
Percentile
19.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00282 · 19.6th percentile
Weakness
CWE-345 · Insufficient Verification of Data Authenticity
Published
2026-08-06T16:16Z
Affected products (3)
ProductVersionsFixed in
apache/cxf< 3.6.123.6.12
apache/cxf≥ 4.0.0, < 4.1.84.1.8
apache/cxf≥ 4.2.0, < 4.2.34.2.3
References (2)
EPSS history
Timeline
  • 06 AUG 11:23Z
    Apache CXF: JwtRequestCodeFilter silently overrides outer PKCE and nonce parameters
    cvelistv5