CVE-2021-22696 Information

Description

CXF supports (via JwtRequestCodeFilter) passing OAuth 2 parameters via a JWT token as opposed to query parameters (see: The OAuth 2.0 Authorization Framework: JWT Secured Authorization Request (JAR)). Instead of sending a JWT token as a equest\ parameter the spec also supports specifying a URI from which to retrieve a JWT token from via the equest_uri\ parameter. CXF was not validating the equest_uri\ parameter (apart from ensuring it uses \https) and was making a REST request to the parameter in the request to retrieve a token. This means that CXF was vulnerable to DDos attacks on the authorization server as specified in section 10.4.1 of the spec. This issue affects Apache CXF versions prior to 3.4.3; Apache CXF versions prior to 3.3.10.

CVSS Vector

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

Reference

https://cxf.apache.org/security-advisories.data/CVE-2021-22696.txt.asc http://www.openwall.com/lists/oss-security/2021/04/02/2 https://lists.apache.org/thread.html/r8651c06212c56294a1c0ea61a5ad7790c06502209c03f05c0c7c9914@%3Cusers.cxf.apache.org%3E https://lists.apache.org/thread.html/r8651c06212c56294a1c0ea61a5ad7790c06502209c03f05c0c7c9914@%3Cdev.cxf.apache.org%3E https://lists.apache.org/thread.html/rec7160382badd3ef4ad017a22f64a266c7188b9ba71394f0d321e2d4@%3Ccommits.cxf.apache.org%3E https://lists.apache.org/thread.html/r6445001cc5f9a2bb1e6316993753306e054bdd1d702656b7cbe59045@%3Cannounce.apache.org%3E https://lists.apache.org/thread.html/rfb87e0bf3995e7d560afeed750fac9329ff5f1ad49da365129b7f89e@%3Ccommits.cxf.apache.org%3E https://www.oracle.com/security-alerts/cpuoct2021.html https://www.oracle.com/security-alerts/cpuapr2022.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

7.5