CVE-2021-22696 OAuth 2 authorization service vulnerable to DDos attacks

2021-04-0210:05:14

CWE-400

CWE-918

apache

www.cve.org

7.7 High

AI Score

Confidence

High

0.003 Low

EPSS

Percentile

71.0%

JSON

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.

CNA Affected

[
  {
    "product": "Apache CXF",
    "vendor": "Apache Software Foundation",
    "versions": [
      {
        "lessThan": "3.4.3",
        "status": "affected",
        "version": "unspecified",
        "versionType": "custom"
      },
      {
        "lessThan": "3.3.10",
        "status": "affected",
        "version": "unspecified",
        "versionType": "custom"
      }
    ]
  }
]