SSRF in Apache Cxf
CVE-2021-22696
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 "request" parameter, the spec also supports specifying a URI from which to retrieve a JWT token from via the "request_uri" parameter. CXF was not validating the "request_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.
Vulnerability class: DoS (Denial of Service)
EPSS: 0.066 (93.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Apache Cxf
- Apache Software Foundation Cxf — versions unspecified
- Oracle Business_intelligence — versions 5.5.0.0.0, 5.9.0.0.0, 12.2.1.3.0
- Oracle Communications_diameter_intelligence_hub
- Oracle Communications_element_manager — versions 8.2.2
- Oracle Communications_session_report_manager
- Oracle Communications_session_route_manager
Weakness classification (CWE)
References
- security@apache.org (x_refsource_MISC, Vendor Advisory)
- security@apache.org (mailing-list, x_refsource_MLIST)
- security@apache.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@apache.org (mailing-list, x_refsource_MLIST)
- security@apache.org (mailing-list, x_refsource_MLIST)
- security@apache.org (mailing-list, x_refsource_MLIST)
- security@apache.org (mailing-list, x_refsource_MLIST)
- security@apache.org (Patch, Third Party Advisory, x_refsource_MISC)
- security@apache.org (Patch, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-22696?
- CVE-2021-22696 is a high-severity vulnerability in Apache Cxf, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2021-04-02.
- How severe is CVE-2021-22696?
- High severity. CVSS v3 base score is 7.5 out of 10.