CVE-2026-63687
Description
A flaw was found in Apache CXF. This vulnerability allows an attacker, who has compromised a client's secret, to bypass critical security protections in the authorization process. By injecting malicious values for parameters like code_challenge and nonce, the attacker can undermine the integrity of Proof Key for Code Exchange (PKCE) and OpenID Connect replay protection, potentially leading to unauthorized access or session hijacking.
Statement
This Important flaw in Apache CXF's JwtRequestCodeFilter allows a security bypass in authorization flows. An attacker with a compromised client secret can manipulate critical authorization parameters, including code_challenge and nonce, to undermine PKCE integrity and OpenID Connect replay protection. This could lead to unauthorized access or session hijacking in applications utilizing affected Red Hat middleware products that rely on these security mechanisms.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.1 | N/A | 9.1 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Understanding the Weakness (CWE)
Confidentiality,Access Control,Availability,Other
Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity; Varies by Context
Attackers can bypass the security decision to access whatever is being protected. The consequences will depend on the associated functionality, but they can range from granting additional privileges to untrusted users to bypassing important security checks. Ultimately, this weakness may lead to exposure or modification of sensitive data, system crash, or execution of arbitrary code.
Frequently Asked Questions
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