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)
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.066 (93.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 93.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.066 · newest: 0.066 · change: 0.000
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
- cxf.apache.org/security-advisories.data/CVE-2021-22696.txt.asc (Vendor Advisory)
- lists.apache.org/thread.html/r8651c06212c56294a1c0ea61a5ad7790c06502209c03f05c0… (mailing-list)
- www.openwall.com/lists/oss-security/2021/04/02/2 (mailing-list, Mailing List, Third Party Advisory)
- lists.apache.org/thread.html/r8651c06212c56294a1c0ea61a5ad7790c06502209c03f05c0… (mailing-list)
- lists.apache.org/thread.html/rec7160382badd3ef4ad017a22f64a266c7188b9ba71394f0d… (mailing-list)
- lists.apache.org/thread.html/r6445001cc5f9a2bb1e6316993753306e054bdd1d702656b7c… (mailing-list)
- lists.apache.org/thread.html/rfb87e0bf3995e7d560afeed750fac9329ff5f1ad49da36512… (mailing-list)
- www.oracle.com/security-alerts/cpuoct2021.html (Patch, Third Party Advisory)
- www.oracle.com/security-alerts/cpuapr2022.html (Patch, Third Party Advisory)
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.